JP2008013725A - Pigment dispersant and printing ink composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pigment dispersant giving low viscosity, high gloss, brilliant color tone, storage stability, and excellent in compatibility with a urethane resin binder. <P>SOLUTION: The pigment dispersant comprises a graft polymer (C) composed of a main chain (A) and a side chain (B), the main chain (A) being constituted by a polyurethane resin (a1) and/or a polyurea resin (a2) having at least one member selected from the group consisting of an amino group, an imino group and a monovalent or divalent aromatic hydrocarbon group, and a side chain (B) being constituted by a polyether skeleton (b1) and/or a polyester skeleton (b2). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pigment dispersant for printing ink and a printing ink composition. More specifically, the present invention relates to a pigment dispersant used for improving dispersibility of a pigment contained in a printing ink composition, and a printing ink composition containing the same.

In general, various pigment dispersants are used in printing ink compositions for the purpose of improving fluidity, gloss of a coating film, clear color tone, and storage stability. Among these dispersants, it is generally known that a polymer chain having an affinity for a solvent and having a site that adsorbs to the pigment particle surface can obtain relatively excellent dispersibility.
As a method of adsorbing to the pigment particle surface, (1) using a so-called acid-base interaction by providing a polar group in the molecule of the dispersing agent, and (2) azo-based benzimidazolone. And organic dye residues such as phthalocyanine, quinacridone, and the like are introduced to give similarity in chemical structure to the pigment particle surface.

About what utilized acid-base interaction, what reacted the polyester compound and polyalkyleneimine (for example, patent document 1) and what reacted polyallylamine (for example, patent document 2) are disclosed, for example. However, it is difficult to use as a general-purpose dispersant because a sufficient dispersion effect cannot be obtained for a pigment such as phthalocyanine having a small polar group on the surface.
In addition, those using organic dye residues such as azo, benzimidazolone, phthalocyanine, and quinacridone have a drawback that the color tone is impaired because they have a dye skeleton.
In order to improve these points, a pigment dispersant obtained by reacting a polyamine compound component modified with an aromatic group and a component containing a lactone is disclosed (Patent Document 3). However, satisfactory values such as the gloss value and storage stability of the coating film have not been obtained, and the dispersibility is insufficient.

JP 61-174939 A Japanese Patent Laid-Open No. 8-38875 JP-A-9-157374

  An object of the present invention is to provide a pigment dispersant which gives low viscosity, high gloss, clear color tone, storage stability and good compatibility with a urethane resin binder.

The inventors of the present invention have reached the present invention as a result of studies to achieve the above object.
That is, the present invention is a graft polymer (C) comprising a main chain (A) and a side chain (B), wherein the main chain (A) is an amino group, an imino group and a monovalent or divalent aromatic. It consists of a polyurethane resin (a1) and / or a polyurea resin (a2) having at least one selected from the group consisting of hydrocarbon groups, and the side chain (B) is a polyether skeleton (b1) and / or a polyester skeleton (b2 A pigment dispersant for printing inks, characterized in that it comprises a graft polymer of
In addition, a diamino compound (D) comprising n imino groups represented by the following general formula (1) and a polyether skeleton (b1) or a polyester skeleton (b2), and an organic isocyanate having two isocyanate groups in the molecule It is a pigment dispersant for printing inks which consists of a polymer (F) formed by making a compound (E) react.

(In the formula, R ₁ and R ₂ each independently represent a linear or branched alkyl group having 1 to 10 carbon atoms, and X ₁ represents either a polyether skeleton (b1) or a polyester skeleton (b2). n represents an integer of 1 to 4.)

The pigment dispersant of the present invention has the following effects.
The printing ink containing the pigment dispersant has low viscosity, high gloss, clear color tone, and storage stability. Furthermore, it has good compatibility with urethane resin and can be used for printing inks using urethane resin binder.

  The pigment dispersant for printing ink of the present invention is a graft polymer (C) comprising a main chain (A) and a side chain (B), and the main chain (A) is a polyurethane resin (a1) and / or polyurea. The resin (a2) is composed of an amino group, an imino group, a monovalent or divalent aromatic hydrocarbon group, or a combination of two or more thereof in the molecular chain. Further, the side chain (B) has a polyether skeleton (b1) and / or a polyester skeleton (b2) in the molecular chain.

The main chain (A) in the graft polymer (C) of the present invention comprises a polyurethane resin (a1), a polyurea resin (a2), and a combination thereof.
The molecular chain has an amino group, an imino group, a monovalent or divalent aromatic hydrocarbon group, or a combination of two or more thereof.

The polyurethane resin (a1) is produced by reacting the organic diisocyanate compound (d) with the diol compound (e), and the polyurea resin (a2) is produced by reacting the organic diisocyanate compound (d) with the polyamine compound (f). Is done.
Further, a urethane / urea resin is produced by a reaction of the diol compound (e) and the polyamine compound (f) with the organic diisocyanate compound (d).

Examples of the organic diisocyanate compound (d) used in the production of the polyurethane resin (a1) of the present invention include a low molecular weight diisocyanate compound (d1), a modified product (d2) of these low molecular weight diisocyanate compounds, these low molecular weight diisocyanate compounds and Examples thereof include a prepolymer (d3) which is a reaction product with an active hydrogen-containing compound and both ends are isocyanate groups; and a combination of two or more of these.

The low molecular weight diisocyanate compound (d1) is an aliphatic diisocyanate having 2 to 12 carbon atoms (excluding carbon in the NCO group; the same applies hereinafter) [ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 2,2,4-trimethylhexane-1,6-diisocyanate, lysine diisocyanate, 2,6-diisocyanatoethylcaproate and the like]; alicyclic diisocyanate having 4 to 15 carbon atoms [isophorone diisocyanate (IPDI), dicyclohexylmethane] Diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, etc.]; aromatic aliphatic diisocyanate having 8 to 12 carbon atoms [xylylene diisocyanate (XDI) and α, α, α ′, α′-tetramethylxylylene diisocyanate (TMXDI), etc.]; aromatic diisocyanates [tolylene diisocyanate (TDI), diethylbenzene diisocyanate, diphenylmethane diisocyanate (MDI) and naphthylene diisocyanate Etc.].

As the modified product (d2) of the low molecular weight diisocyanate compound, the modified product of the low molecular weight diisocyanate compound (d1) (carbodiimide group, uretdione group, uretoimine group, urethane group, urea group, burette group, isocyanurate group, etc.) Modified product).

Furthermore, the prepolymer (d3) having both ends of an isocyanate group that can be used in the present invention is a reaction product of the aforementioned low molecular weight diisocyanate compound (d1) and two active hydrogen-containing compounds (g) in the molecule. And a prepolymer having two isocyanate groups in the molecule.

The two active hydrogen-containing compounds (g) in the molecule used here are not particularly limited, but low molecular diol (e1), high molecular diol (e2), polyether diol (e21), which will be described in detail later, Polyester diol (e22), polydiene diol (e23), etc .; and mixtures of two or more thereof can be used.

The prepolymer (d3) whose both ends are isocyanate groups has a low molecular weight diisocyanate compound (d1) and two active hydrogen-containing compounds (g) in the molecule, and the equivalent ratio of (d1) / (g) is usually It is obtained by reacting at 1.2 to 10/1, preferably 1.2 to 5/1.
For example, using MDI as (d1) and poly (neopentyl alcohol / adipate) diol as (g), the equivalent ratio of (d1) / (g) is 1.5 / 1, and the reaction is carried out at 80 ° C. for 6 hours. Can be exemplified.

In the production of (d3), in order to accelerate the reaction, a catalyst usually used for the production of polyurethane can be used as necessary. Examples of such catalysts include organometallic compounds (for example, dibutyltin dilaurate, dioctyltin dilaurate, lead octoate, bismuth octoate); tertiary amines (for example, triethylenediamine, trialkylamines having 1 to 8 carbon atoms in an alkyl group (for example, Triethylamine), diazabicycloalkenes (for example, 1,8-diazabicyclo [5,4,0] undecene-7)]; and combinations of two or more thereof. The amount of the catalyst used is usually 2% by weight or less, preferably 0.001 to 1% by weight, based on the weight of (d3).

Among the organic diisocyanate compounds (d), preferred are aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates and prepolymers (d3), and in particular, monovalent or divalent aromatics in the main chain (A). In terms of being able to introduce a hydrocarbon group, aromatic diisocyanates and prepolymers using aromatic diisocyanates are preferred, and TDI, MDI and prepolymers using these are more preferred.

Examples of the diol compound (e) used in the production of the polyurethane resin (a1) of the present invention include a low molecular diol (e1), a high molecular diol (e2), and a combination thereof.

The low molecular diol (e1) includes a divalent diol having a hydroxyl group equivalent (molecular weight per hydroxyl group measured by hydroxyl group value measurement; hereinafter the same) of less than 250.
Examples of the low molecular diol (e1) include the following (1) to (3).
(1) C2-C12 aliphatic diols;
Linear diols (such as ethylene glycol, diethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol) and branched diols (1,2-propylene) Glycol, neopentyl glycol, 3-methyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol, 1,2-, 1,3- and 2,3-butanediol and 1,2 -Decanediol, etc.).
(2) Diols having a cyclic group having 6 to 25 carbon atoms;
For example, those described in JP-B-45-1474; alicyclic group-containing diols such as 1,4-bis (hydroxymethyl) cyclohexane and hydrogenated bisphenol A [1,4-bis (hydroxymethyl) cyclohexane and hydrogenated bisphenol A, etc. And diols containing aromatic rings [m-xylylene glycol, p-xylylene glycol, dihydric phenols [monocyclic dihydric phenols (hydroquinone, etc.), bisphenols (phenol A, bisphenol S, bisphenol F, etc.) and dihydroxynaphthalene Etc.] of alkylene oxide (hereinafter abbreviated as AO) adduct (hydroxyl equivalent less than 250), bishydroxyalkyl (2 to 4 carbon atoms) ester of aromatic dicarboxylic acid [bis (2-hydroxyethyl) terephthalate, etc.] Such〕.
(3) Tertiary amino group-containing diol;
For example, hydrocarbyl dialkanolamines [primary monoamines [for example, aliphatic or alicyclic primary monoamines having 1 to 12 carbon atoms (methylamine, ethylamine, cyclopropylamine, 1-propylamine, 2-propylamine, amylamine] , Isoamylamine, hexylamine, 1,3-dimethylbutylamine, 3,3-dimethylbutylamine, 2-aminoheptane, 2-aminoheptane, 3-aminoheptane, cyclopentylamine, cyclohexylamine, heptylamine, nonylamine, decylamine and dodecyl Bishydroxyalkylated products (such as AO2 mole adducts having 2 to 4 carbon atoms)] of aromatic primary monoamines having 6 to 12 carbon atoms (aniline, benzylamine and the like)].
If necessary, a trivalent polyol may be used in combination with a part of the diol (e) component.
Examples of the trivalent polyol include glycerin, trimethylolpropane and their AO adducts (hydroxyl equivalent is less than 250); and mixtures of two or more thereof.

In the above-mentioned low molecular diel (e1) and the later-described high molecular diel (e2), AO includes an alkylene oxide having 2 to 10 or more carbon atoms and a phenyl or halo substituent thereof, and ethylene oxide (hereinafter referred to as EO). ), 1,2-propylene oxide (hereinafter abbreviated as PO), 1,2-, 1,3-, 1,4- and 2,3-butylene oxide, styrene oxide, carbon number 5 -10 or more α-olefin oxides, epihalohydrins (such as epichlorohydrin) and combinations of two or more thereof (block and / or random addition).
Preference is given to EO, PO and combinations thereof (block and / or random addition).

Examples of the polymer diol (e2) include a polyether diol (e21), a polyester diol (e22), a polydiene diol (e23), and a mixture of two or more thereof.
The hydroxyl equivalent of (e2) is usually 250 to 2,000, preferably 300 to 1,500, and the number of functional groups is usually 2 to 4, preferably 2 to 3, and 2 is particularly preferred.

Examples of the polyether diol (e21) include compounds having a structure in which AO is added to the low molecular diol (e1).
Specific examples of the polyether diol (e21) include polyethylene glycol, polypropylene glycol, polyoxyethylene-polyoxypropylene (block and / or random) glycol, polytetramethylene ether glycol, polyoxybutylene-polyoxyethylene (block and And / or random) glycols, polyoxybutylene-polyoxypropylene (block and / or random) glycols, EO and / or PO adducts of bisphenol A, and combinations of two or more thereof.

Examples of the polyester diol (e22) include (1) those obtained by condensation polymerization of the low molecular weight diol (e1) and / or the polyether diol (e21) and a dicarboxylic acid; (2) the low molecular weight diol (e1) and / or A ring-opening addition of a lactone monomer to a polyether diol (e21); (3) condensation polymerization of the low molecular diol (e1) and / or the polyether diol (e21) with a carbonic acid diester (dimethyl carbonate, ethylene carbonate, etc.) And mixtures of two or more thereof. The polyether diol (e21) preferably has a hydroxyl group equivalent of 500 or less.

Specific examples of the dicarboxylic acid of (1) above include aliphatic dicarboxylic acids having 4 to 15 carbon atoms (such as succinic acid, adipic acid, sebacic acid, glutaric acid, azelaic acid, maleic acid and fumaric acid), carbon number 8 To 15 aromatic dicarboxylic acids [such as terephthalic acid and isophthalic acid], ester-forming derivatives thereof [acid anhydrides, lower alkyl (carbon number 1 to 4) esters and acid halides (such as acid chlorides)] and the like The mixture of 2 or more types is mentioned.

Examples of the lactone monomer (2) include lactones having 4 to 12 carbon atoms such as γ-butyrolactone, ε-caprolactone, γ-valerolactone, and mixtures of two or more thereof.

Specific examples of the polyester diol (e22) include polyethylene adipate diol, polybutylene adipate diol, polyhexamethylene adipate diol, polybutylene isophthalate diol, polyhexamethylene isophthalate diol, polyneopentyl adipate diol, polyethylene propylene adipate diol, Examples include polyethylene butylene adipate diol, polybutylene hexamethylene adipate diol, poly (polytetramethylene ether) adipate diol, poly (diethylene glycol) isophthalate diol, polycaprolactone diol, polyhexamethylene carbonate diol, and combinations of two or more thereof. .

Examples of the polydiene diol (e23) include polybutadiene diol, polyisoprene diol, partial or complete hydrides thereof (hydrogenation rate is, for example, 20 to 100 mol%), and combinations of two or more thereof.

Among these polymer diols (e2), polyether diol (e21) and polyester diol (e22) are preferable, and polyester diol (e22) is more preferable.

Particularly, in order to introduce an amino group, an imino group, a monovalent or divalent aromatic hydrocarbon group into the main chain (A), an aromatic ring-containing diol, a tertiary amino group in the low molecular diol (e1) Containing diols are preferred, and in the polymer diol (e2), ester-forming derivatives of aromatic dicarboxylic acids are preferred.

As the organic diisocyanate compound (d) used for the production of the polyurea resin (a2) of the present invention, the same organic diisocyanate compound (d) used for the production of the polyurethane resin (a1) can be used.
In particular, aromatic aliphatic organic diisocyanates and aromatic organic diisocyanates are preferred in order to introduce a monovalent or divalent aromatic hydrocarbon group into the main chain (A).

As a polyamine compound (f) used for manufacture of the polyurea resin (a2) of this invention, C2-C20 diamine is mentioned.
For example, aliphatic diamines (alkylene diamines such as ethylene diamine, trimethylene diamine, hexamethylene diamine, heptamethylene diamine, octamethylene diamine and decamethylene diamine); alicyclic diamines (such as dicyclohexylmethane diamine and isophorone diamine); aromatic diamines ( Phenylenediamine, tolylenediamine, diethyltolylenediamine, diphenylmethanediamine, diphenyletherdiamine, etc.); araliphatic diamines (xylylenediamine, etc.) and the like.
In particular, an aromatic diamine is preferable in order to introduce an amino group, imino group, monovalent or divalent aromatic hydrocarbon group into the main chain (A).

The polyurethane resin (a1) of the present invention can be produced by a usual method by reaction of organic diisocyanate (d) and polymer diol (e). The polyurethane resin is obtained by reacting (d) and (e), but the terminal isocyanate group remaining unreacted may be reacted with a reaction terminator to seal the terminal.

In the production of polyurethane resin and polyurea resin, a reaction terminator can be used as necessary. Examples of the terminator include monohydric alcohols and monoamines.
Specific examples of monohydric alcohols include aliphatic monohydric alcohols having 1 to 10 carbon atoms (methanol, ethanol, propanol, butanol, octanol, ethyl cellosolve, ethyl carbitol, etc.); alicyclic 1 having 6 to 10 carbon atoms Monohydric alcohols (cyclohexanol, etc.); monocyclic alcohols having 7-20 carbon atoms (benzyl alcohol, hydroxyethylbenzene; (poly) oxyalkylenes of monohydric phenols (phenol, cresol, etc.) (carbon number of alkylene group 2) -4, degree of polymerization 1-5) ether, etc.]; and mixtures of two or more thereof.
Specific examples of the monoamine include mono- and dialkylamines having 1 to 10 carbon atoms in the alkyl group (such as methylamine, ethylamine, diethylamine, n-butylamine and di-n-butylamine); alicyclic monoamines having 6 to 10 carbon atoms. (Cyclohexylamine etc.); C6-C15 aromatic ring-containing monoamine (Benzylamine and aniline etc.); C4-C10 heterocyclic monoamine (Morpholine etc.), Monoalkyl of C2-C4 of hydroxyalkyl group -And dialkanolamines (such as monoethanolamine, diethanolamine and diisopropanolamine); and mixtures of two or more thereof.
Of these, preferred are aliphatic monohydric alcohols and mono- and dialkylamines.

Moreover, in order to accelerate | stimulate reaction, the catalyst normally used for a polyurethane can be used if necessary. As this catalyst, the same catalyst as described above in the method for producing a prepolymer (d3) having both ends being isocyanate groups can be used.

The polyurea resin (a2) of the present invention can be produced by a conventional method by the reaction of a low molecular weight diisocyanate compound (d1) and / or a modified product (d2) of a low molecular weight diisocyanate compound and a polyamine compound (f). Similarly to the polyurethane resin (a1), if necessary, the terminal isocyanato group may be reacted with the same reaction terminator as described above.
Moreover, urethane / urea resin can be manufactured by reaction of the prepolymer (d3) which is an isocyanate group at both ends, and a polyamine compound (f), and you may make it react with a stopper as needed.

In the production of the polyurethane resin (a1) and the polyurea resin (a2), the equivalent ratio of the NCO group of the organic diisocyanate (d) to the active hydrogen-containing group of the polymer diol (e) and the polyamine compound (f) is usually 0.7. : 1 to 1.2: 1, preferably 0.8: 1 to 1.1: 1.

The production methods (a1) and (a2) can be carried out in the presence or absence of an organic solvent.
Organic solvents that can be used in the reaction in the presence of organic solvents include ketones (such as acetone and methyl ethyl ketone methyl isobutyl ketone), esters (such as ethyl acetate, propyl acetate, and butyl acetate), ethers (such as tetrahydrofuran), Aromatic hydrocarbons (toluene, xylene, etc.), alcohols (methanol, ethanol, isopropyl alcohol, etc.), polyhydric alcohol derivatives (ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, etc.), amides (dimethylformamide, etc.) sulfoxide (Such as dimethyl sulfoxide) and a mixed solvent of two or more thereof.
Among these, acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, propyl acetate, butyl acetate, tetrahydrofuran, toluene, xylene, methanol, ethanol, isopropyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether and these These are two or more mixed solvents.
The amount of the solvent used is such that the weight ratio of the polyurethane resin (A) to the solvent is usually in the range of 100/0 to 10/90, preferably 80/20 to 20/80.

  In the production of (a1) and (a2), the reaction temperature may be the same as that usually employed for the polyurethane and polyureaization reaction, usually 20 to 100 ° C. when a solvent is used, and usually 20 to 20 when no solvent is used. 220 ° C.

  The number average molecular weight of the main chain (A) in the graft polymer (C) of the present invention is usually 500 to 500,000, preferably 1000 to 200,000, and more preferably 2000 to 10,000. When the number average molecular weight is within this range, the pigment dispersibility is good.

The content of the aromatic ring in the main chain (A) in the graft polymer (C) of the present invention is usually 10 to 90% by weight, preferably 20 to 60% by weight, more preferably 30 to 50% by weight. %. When the content of the aromatic ring is within this range, the pigment dispersibility is good.

The amine value in the main chain (A) in the graft polymer (C) of the present invention is usually 1-1000, preferably 10-500, more preferably 50-300. When the amine value is within this range, the pigment dispersibility is good.

The side chain (B) in the graft polymer (C) of the present invention is derived from the polyether skeleton (b1) alone, the polyester skeleton (b2) alone, or both the polyether skeleton (b1) and the polyester skeleton (b2). Become.

Examples of the polyether skeleton (b1) in the side chain (B) in the graft polymer (C) of the present invention include those containing in the molecule a polyether chain formed by adding the AO. Specific examples of the addition of AO include those similar to AO described above in the description of the low molecular diol (e1).

Examples of the polyester skeleton (b2) in the side chain (B) in the graft polymer (C) of the present invention include those containing any of the following polyester chains consisting of (1) to (3) in the molecule. .
(1) Condensation polymerization of the low molecular diol (e1) and / or polyether diol (e21) and dicarboxylic acid (2) Ring-opening addition of a lactone monomer (3) The low molecular diol (e1) and / Or by condensation polymerization of a polyether diol (e21) and a carbonic acid diester (dimethyl carbonate, ethylene carbonate, etc.) Specific examples of the dicarboxylic acid (1) and the lactone monomer (2) include polyester diol ( The thing similar to what was mentioned above by description of e22) is mentioned.

  The number average molecular weight of the side chain (B) in the graft polymer (C) of the present invention is usually 500 to 100,000, preferably 700 to 10,000, and more preferably 1000 to 50,000. When the number average molecular weight is within this range, pigment dispersibility and dispersion stability are improved.

  Further, the pigment dispersant for printing ink of the present invention comprises a diamino compound (D) comprising n imino groups represented by the following general formula (1) and a polyether skeleton (b1) or a polyester skeleton (b2), and a molecule. It is characterized by comprising a polymer (F) obtained by reacting an organic isocyanate compound (E) having two isocyanate groups therein.

(In the formula, R ₁ and R ₂ each independently represent a linear or branched alkyl group having 1 to 10 carbon atoms, and X ₁ represents either a polyether skeleton (b1) or a polyester skeleton (b2). n represents an integer of 1 to 4.)

  As the diamino compound (D) comprising the n imino groups represented by the general formula (1) and the polyether skeleton (b1) or the polyester skeleton (b2), a diamino compound having a polyether skeleton (b1) in the molecule (D1) and the diamino compound (D2) which has a polyester frame | skeleton (b2) in a molecule | numerator are mentioned.

The diamino compound (D1) having a polyether skeleton (b1) in the molecule can be produced by adding the AO to an imino group.
Specific examples of the addition of AO include those similar to AO described above in the description of the low molecular diol (e1).

  The diamino compound (D2) having a polyester skeleton (b2) in the molecule can be produced by ring-opening addition of the lactone monomer to an imino group. Examples of the lactone monomer include lactones having 4 to 12 carbon atoms such as γ-butyrolactone, ε-caprolactone, γ-valerolactone, and mixtures of two or more thereof.

The number average molecular weight of X ₁ consisting of either the polyether skeleton (b1) or the polyester skeleton (b2) in the diamino compound (D) is 500 to 100,000, preferably 700 to 10,000, more preferably 1,000 to 5,000.

R ₁ and R ₂ in the diamino compound (D) each independently independently represent a linear or branched alkyl group having 1 to 10 carbon atoms, preferably 2 to 3 carbon atoms. Specific examples include methylene, ethylene, n-propylene, i-propylene, n-butylene, sec-butylene, t-butylene, n-pentamethylene, neopentamethylene, 3-methyl-pentamethylene, n-hexamethylene, Examples thereof include 2-ethylhexamethylene, octamethylene, decamethylene and the like, and ethylene and propylene are preferable.

The repeating unit n in the diamino compound (D) is usually an integer of 1 to 4, preferably 1 or 2.

The amine compound (D1 ′), which is a raw material before AO addition in (D1), and the amine compound (D2 ′), which is a raw material before ring-opening addition of a lactone monomer in (D2), are primary at both ends. An alkylene amine having an amino group and having n secondary imino groups in the molecular chain can be mentioned.
For example, alkylene triamines in which n is 1 [diethylenetriamine, bis (3-aminopropyl) amine, bis (hexamethylene) triamine, etc.]; alkylenetetramines in which n is 2 (triethylenetetramine, etc.); Specific alkylenepentamines (tetraethylenepentamine, etc.); alkylenehexamines where n is 4 (pentaethylenehexamine, etc.). Of these, diethylenetriamine and triethylenetetramine are preferred.

As the organic isocyanate compound (E) having two isocyanate groups in the molecule to be reacted with the diamino compound (D), the same organic diisocyanate compound (d) can be used. In terms of being able to introduce a divalent aromatic hydrocarbon group, aromatic diisocyanates and prepolymers using aromatic diisocyanates are preferable, and TDI, MDI and prepolymers using these are more preferable.

As the pigment that can be used in the present invention, all pigments that are usually used in printing inks can be used, and examples thereof include organic pigments and inorganic pigments. Specific examples of organic pigments include phthalocyanines, insoluble azo pigments, azo lake pigments, condensed polycyclic pigments (slen, indigo, perylene, perinone, phthalone, dioxazine, quinacridone, isoindolinone, Diketopyrrolopyrrole pigments) and the like, and inorganic pigments include various pigments such as titanium oxide, zinc oxide, lithopone, calcium carbonate, carbon black, graphite, bengara, yellow lead, yellow iron oxide and the like.

  The pigment is preferably blended in an amount of 0.01 to 1000 parts by weight with respect to 1 part by weight of the pigment dispersant. If it is less than 0.01 part by weight, the pigment concentration is too low and the coloring function is lowered. On the other hand, if the amount exceeds 1000 parts by weight, the pigment is not sufficiently dispersed, and a stable pigment dispersion cannot be obtained.

As the binder resin used in the printing ink composition of the present invention, general inks and paint resins can be used. For example, polyurethane resin, polyurea resin, polyurethane urea resin, polyester resin, polyether resin, polycarbonate resin, epoxy resin, amino resin, acrylic resin, melamine resin, amide resin, phenol resin, vinyl resin, etc., these resins May be added alone or as a mixture of a plurality of resins.

As the solvent used in the printing ink composition of the present invention, the organic solvents described above in the production methods (a1) and (a2) can be used alone or in admixture of two or more. Preferably, it is a single solvent or a mixed solvent of two or more selected from ethyl acetate, propyl acetate, isopropyl alcohol, toluene, and methyl ethyl ketone.

In the printing ink composition of the present invention, additives such as an abrasion resistance improver, a plasticizer, and a crosslinking agent can be used as necessary.

The printing ink composition of the present invention can be produced by kneading the above components using a normal printing ink production apparatus such as a ball mill, an attritor, or a sand mill.

  Examples and the like according to the present invention will be described below, but the present invention is not limited to these. “Parts” indicates parts by weight.

  The following method produced a diamino compound having a polyether skeleton and a polyester skeleton in the molecule of the present invention, a dispersant, and a dispersant for comparison.

Production Example 1-1
Stirrer, pressure gauge, pressure drop funnel, vacuum pump, 272 parts of ketimine compound (G-1) obtained by reacting pre-manufactured diethylenetriamine and methylisobutylketone with a stainless steel autoclave equipped with temperature control function, water 0.50 part of potassium oxide was added, and the inside of the mixed system was replaced with nitrogen.
Next, at 100 to 120 ° C., 895 parts of ethylene oxide was introduced so that the gauge pressure was −0.1 to 0.5 MPa, and an ethylene oxide adduct (H-1) of a ketimine compound (G-1) was obtained. It was. The reaction time from the start of blowing ethylene oxide to the end of the reaction was 8 hours.
Furthermore, after adding 300 parts of water and stirring at 100 degreeC for 1 hour and hydrolyzing (H-1), the produced | generated methyl isobutyl ketone and water were the same temperature under -0.1-0MPa, 4 Removal with time gave diethylenetriamine ethylene oxide adduct (D-1), which is the diamino compound of the present invention.

Production Example 1-2
A reaction vessel equipped with a stirrer was charged with 67.3 parts of TDI and 490 parts of ethyl acetate, and then 198.5 parts of an ethylene oxide adduct (D-1) of diethylenetriamine obtained in Production Example 1-1 and isopropanol. A mixture of 210 parts was dropped and reacted at room temperature for 30 minutes, and then 34.2 parts of di-n-butylamine was added and reacted at room temperature for 30 minutes to give a pigment dispersant of the present invention having a resin concentration of 30%. (C-1) 1000 parts of a solution was obtained.
The number average molecular weight of the main chain (A) of this pigment dispersant (C-1) is about 700, the number average molecular weight of the side chain (B) is about 680, and the aromatic ring concentration in the main chain (A) is 32% by weight. The amine value was 153.

Production Example 2-1
A ketimine compound (G-2) obtained by reacting pentaethylenehexamine and methyl isobutyl ketone prepared in advance in a stainless steel autoclave equipped with a stirrer, a pressure gauge, a pressure dropping funnel, a vacuum pump, and a temperature control function 46. 4 parts and 0.40 part of potassium hydroxide were added, and the inside of the mixed system was replaced with nitrogen.
Next, at 100 to 120 ° C., a mixture of 581 parts of ethylene oxide and 766 parts of propylene oxide was introduced so that the gauge pressure was −0.1 to 0.5 MPa, and the ethylene / propylene oxide of ketimine compound (G-2) was introduced. An adduct (H-2) was obtained. The reaction time from the start of blowing ethylene oxide and propylene oxide to the end of the reaction was 16 hours.
Furthermore, after adding 300 parts of water and stirring at 100 degreeC for 1 hour and hydrolyzing (H-2), the produced | generated methyl isobutyl ketone and water were the same temperature under -0.1-0MPa, 4 Removal with time gave an ethylene / propylene oxide adduct (D-2) of pentaethylenehexamine, which is a diamino compound of the present invention.

Production Example 2-2
A reaction vessel equipped with a stirrer was charged with 6.0 parts of MDI and 490 parts of ethyl acetate, and then 294 parts of an ethylene / propylene oxide adduct (D-2) of pentaethylenehexamine obtained in Production Example 2-1. And a mixture of 210 parts of isopropanol are allowed to react at room temperature for 30 minutes, and then 0.07 part of di-n-butylamine is added and reacted at room temperature for 30 minutes to give a pigment dispersion of the present invention having a resin concentration of 30%. 1000 parts of an agent (C-2) solution was obtained.
The number average molecular weight of the main chain (A) of this pigment dispersant (C-2) is about 450,000, the number average molecular weight of the side chain (B) is about 3,000, and the aromatic ring concentration in the main chain (A). Was 32% by weight and the amine value was 467.

Production Example 3-1
In a stainless steel autoclave equipped with a stirrer, a pressure gauge, a pressure dropping funnel, a vacuum pump, and a temperature control function, 136 parts of the ketimine compound (G-1) used in Production Example 1-1 and 0.25 parts of potassium hydroxide were added. The mixed system was replaced with nitrogen.
Next, at 100 to 120 ° C., a mixture of 1008 parts of tetrahydrofuran was introduced so that the gauge pressure was −0.1 to 0.5 MPa, and a tetramethylene oxide adduct (H-3) of the ketimine compound (G-1) was introduced. Got. The reaction time from the start of blowing tetrahydrofuran to the end of the reaction was 12 hours.
Furthermore, after adding 300 parts of water and stirring at 100 degreeC for 1 hour and hydrolyzing (H-3), the produced | generated methyl isobutyl ketone and water were the same temperature under -0.1-0MPa, 4 Removal with time gave a tetramethylene oxide adduct (D-3) of diethylenetriamine, which is a diamino compound of the present invention.

Production Example 3-2
A reaction vessel equipped with a stirrer was charged with 10.7 parts of MDI, 18.9 parts of isophorone diisocyanate and 490 parts of ethyl acetate, and then the tetramethylene oxide adduct (D-) of diethylenetriamine obtained in Production Example 3-1. 3) A mixture of 270 parts and 210 parts of isopropanol was added and reacted at room temperature for 30 minutes, and then 0.1 part of di-n-butylamine was added and reacted at room temperature for 30 minutes. 1000 parts of the pigment dispersant (C-3) solution of the invention was obtained.
The number average molecular weight of the main chain (A) of this pigment dispersant (C-3) is 200,000, the number average molecular weight of the side chain (B) is 2,000, and the aromatic ring concentration in the main chain (A) is 15 The weight percentage and amine value were 168.

Production Example 4-1
In a stainless steel autoclave equipped with a stirrer, pressure gauge, pressure-resistant dropping funnel, vacuum pump, temperature control function, 68 parts of ketimine compound (G-1) used in Production Example 1-1, 1254 parts of ε-caprolactone monomer, mono 0.13 part of butylhydroxytin oxide was charged, the inside of the mixed system was replaced with nitrogen, and the reaction was carried out at 160 ° C. until the caprolactone monomer was 1% or less, and a polycaprolactone adduct (H) of the ketimine compound (G-1) -4) was obtained. The reaction time was 6 hours.
Furthermore, after adding 300 parts of water and stirring at 100 degreeC for 1 hour and hydrolyzing (H-4), the produced | generated methyl isobutyl ketone and water are the same temperature, -0.1-0MPa under 4 Removal with time gave a polycaprolactone adduct (D-4) of diethylenetriamine, which is a diamino compound of the present invention.

Production Example 4-2
A reaction vessel equipped with a stirrer and a thermometer was charged with 50.2 parts of polyneopentyl adipate diol (hydroxyl value 234.2) and 37.7 parts of MDI, reacted at 80 ° C. for 6 hours, and an NCO content of 4.80. % Of urethane prepolymer was obtained.
Next, 490 parts of ethyl acetate was added to uniformly dissolve this prepolymer, and then a mixture comprising 209.8 parts of polycaprolactone adduct (D-4) of diethylenetriamine obtained in Production Example 4-1 and 210 parts of isopropanol. The mixture was reacted at room temperature for 30 minutes, and then 2.4 parts of di-n-butylamine was added and reacted at room temperature for 30 minutes to obtain a pigment dispersant (C-4) solution of the present invention having a resin concentration of 30%. 1000 parts were obtained.
The number average molecular weight of the main chain (A) of this pigment dispersant (C-4) is 10,000, the number average molecular weight of the side chain (B) is 5,000, and the aromatic ring concentration in the main chain (A) is 25. The weight percentage and amine value were 25.

Production Example 5-1
35.4 parts of ketimine compound (G-1) used in Production Example 1-1 and ε-caprolactone in a 2 liter stainless steel autoclave equipped with a stirrer, pressure gauge, pressure dropping funnel, vacuum pump, and temperature control function 682 parts of monomer, 598 parts of γ-valerolactone monomer and 0.13 part of monobutylhydroxytin oxide were charged, the inside of the mixed system was replaced with nitrogen, and the reaction was carried out at 160 ° C. until the caprolactone monomer was 1% or less. A polycaprolactone / valerolactone adduct (H-5) of compound (G-1) was obtained. The reaction time was 6 hours.
Furthermore, after adding 300 parts of water and stirring at 100 degreeC for 1 hour and hydrolyzing (H-5), the produced | generated methyl isobutyl ketone and water were the same temperature under -0.1-0MPa, 4 Removal with time gave a polycaprolactone / valerolactone adduct (D-5) of diethylenetriamine, which is a diamino compound of the present invention.

Production Example 5-2
A reaction vessel equipped with a stirrer and a thermometer was charged with 38.6 parts of EO addition product of bisphenol A [trade name; Newpol BPE-20, manufactured by Sanyo Chemical Industries] and 32.5 parts of isophorone diisocyanate at 130 ° C. For 5 hours to obtain 71.2 parts of urethane prepolymer having an NCO content of 2.88%.
Next, after adding 490 parts of toluene and uniformly dissolving the prepolymer, from 228.5 parts of the polycaprolactone / valerolactone adduct (D-5) of diethylenetriamine obtained in Production Example 5-1, and 210 parts of isopropanol. And then reacting at room temperature for 30 minutes, and then adding 0.38 part of di-n-butylamine and reacting at room temperature for 30 minutes. The pigment dispersant of the present invention having a resin concentration of 30% (C-5) ) 1000 parts of a solution were obtained.
The number average molecular weight of the main chain (A) of this pigment dispersant (C-5) is 50,000, the number average molecular weight of the side chain (B) is 9,800, and the aromatic ring concentration in the main chain (A) is 25. The weight percent and amine value were 18.

Production Example 6-1
In a 2 liter stainless steel autoclave equipped with a stirrer, a pressure gauge, a pressure dropping funnel, a vacuum pump, and a temperature control function, 136 parts of the ketimine compound (G-1) used in Production Example 1-1, 0. 25 parts were charged, and the inside of the mixed system was replaced with nitrogen. Next, at 100 to 120 ° C., 1073 parts of propylene oxide was introduced so that the gauge pressure was −0.1 to 0.5 MPa, and a propylene oxide adduct (H-6) of (G-1) was obtained. The reaction time from the start of propylene oxide blowing to the end of the reaction was 6 hours.
Furthermore, after adding 300 parts of water and stirring at 100 degreeC for 1 hour and hydrolyzing (H-6), the produced | generated methyl isobutyl ketone and water are the same temperature, -0.1-0MPa under 4 Removal with time gave a propylene oxide adduct (D-6) of diethylenetriamine, which is a diamino compound of the present invention.

Production Example 6-2
A reaction vessel equipped with a stirrer and a thermometer was charged with 58.7 parts of EO product of bisphenol A (Newpol BPE-20) and 69.7 parts of MDI, reacted at 80 ° C. for 6 hours, and an NCO content of 6. 128.4 parts of 07% urethane prepolymer were obtained.
Next, after adding 490 parts of toluene and uniformly dissolving the prepolymer, a mixture of 164.9 parts of propylene oxide adduct (D-6) of diethylenetriamine obtained in Production Example 6-1 and 210 parts of isopropanol was prepared. The mixture was allowed to react at room temperature for 30 minutes, and then 6.66 parts of di-n-butylamine was added and reacted at room temperature for 30 minutes to obtain a pigment dispersant (C-6) solution 1000 of the present invention having a resin concentration of 30%. Got a part.
The number average molecular weight of the main chain (A) of this pigment dispersant (C-6) is 5,000, the number average molecular weight of the side chain (B) is 2,200, and the aromatic ring concentration in the main chain (A) is 52. The% by weight and the amine value were 36.

Comparative production example 1
A reaction vessel equipped with a stirrer is charged with 199.2 parts of MDI and 490 parts of toluene, and then 86.8 parts of N- (2-aminoethyl) -N-methyl-1,2-ethanediamine and 210 parts of isopropanol. A mixture of the following was added and reacted at room temperature for 30 minutes, and then 14.2 parts of di-n-butylamine was added and reacted at room temperature for 30 minutes to obtain a pigment dispersant (I-1) solution having a resin concentration of 30%. 1000 parts were obtained. The number average molecular weight of the main chain (A) of this pigment dispersant (I-1) was 5,000, the aromatic ring concentration in the main chain (A) was 44% by weight, and the amine value was 151.

Comparative Production Example 2-1
Ketimine compound obtained by reacting 1,3-diamino-2-propanol and methyl isobutyl ketone in a 2 liter stainless steel autoclave equipped with a stirrer, pressure gauge, pressure drop funnel, vacuum pump, temperature control function ( G-3) 54.0 parts and 0.30 part of potassium hydroxide were added, and the inside of the mixed system was replaced with nitrogen. Next, at 100 to 120 ° C., 1288 parts of propylene oxide was introduced so that the gauge pressure was −0.1 to 0.5 MPa, and a propylene oxide adduct (H-7) of (G-3) was obtained. The reaction time from the start of propylene oxide blowing to the end of the reaction was 6 hours. Furthermore, after adding 300 parts of water and stirring at 100 degreeC for 1 hour and hydrolyzing (H-7), the produced | generated methyl isobutyl ketone and water are the same temperature, -0.1-0MPa under 4 Removal with time gave a propylene oxide adduct (J-1) of 1,3-diamino-2-propanol.

Comparative Production Example 2-2
A reaction vessel equipped with a stirrer and a thermometer was charged with 81.0 parts of polyneopentyl adipatediol (hydroxyl value 234.2) and 53.9 parts of isophorone diisocyanate and reacted at 130 ° C. for 6 hours. 134.9 parts of 0.04% urethane prepolymer were obtained. Next, after adding 490 parts of ethyl acetate and dissolving uniformly, 161.5 parts of propylene oxide adduct (J-1) of 1,3-diamino-2-propanol obtained in Comparative Production Example 2-1 and isopropanol were obtained. A mixture consisting of 210 parts was charged and reacted at room temperature for 30 minutes, and then 3.6 parts of di-n-butylamine was charged and reacted at room temperature for 30 minutes to obtain a pigment dispersant (I-2 with a resin concentration of 30%). ) 1000 parts of a solution were obtained. The number average molecular weight of the main chain (A) of this pigment dispersant (I-2) was 10,000, the number average molecular weight of the side chain (B) was 2,300, and the amine number in the main chain (A) was 0. It was.

Comparative production example 3
A reactor equipped with a stirrer, reflux condenser, nitrogen inlet tube and temperature control function was charged with 565 parts of caprolactone monomer, 11.6 parts of caproic acid, 423 parts of 4-methylcaprolactone, 0.1 part of tetrabutyl titanate, and nitrogen. It was made to react at 170 degreeC under airflow. After the caprolactone monomer became 1% or less, it was heated at 210 ° C. until a predetermined oxidation was achieved. The resulting polycaprolactone had an oxidation of 5.8.
Next, 110 parts of polyallylamine [(trade name PAA-10C (molecular weight 10,000), manufactured by Nitto Boseki Co., Ltd.)] was charged and reacted at 120 ° C., and a pigment dispersant (I-3) for comparative evaluation was added. Obtained.
In this pigment dispersant (I-3), the main chain is a polyallylamine having a molecular weight of 10,000, and the side chain is a polyester mainly composed of polycaprolactone having a molecular weight of about 1,200.

Comparative production example 4
In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a temperature control function, 100 parts of polyethyleneimine [trade name SP-200 (molecular weight 10,000), manufactured by Nippon Shokubai Co., Ltd.] and β-naphthoic acid 15 The parts were charged and reacted at 150 ° C. under a nitrogen stream. When 1.6 parts of water was distilled, the mixture was cooled to 60 ° C., 885 parts of acrylic group-containing polycaprolactone [trade name: PCLFA-12 (molecular weight 1,400), manufactured by Daicel Chemical Industries, Ltd.] was charged, ¹ H- The reaction was continued until the double bond signal disappeared by NMR measurement, and a pigment dispersant (I-4) for comparative evaluation was obtained.
In this pigment dispersant (I-4), the main chain is polyethyleneimine having a molecular weight of 10,000, and the side chain is polyester mainly composed of polycaprolactone having a molecular weight of about 1,400. 0

Example 1
20 parts of copper phthalocyanine pigment (CIPigument Blue 15: 3), 20 parts of 30% solution of pigment dispersant (C-1) obtained in Production Example 1, 42 parts of ethyl acetate, 18 parts of isopropyl alcohol, and 300 parts of steel beads, respectively Weighed and dispersed with a paint conditioner for 3 hours to obtain a pigment dispersion. Using the obtained pigment dispersion, the 60-degree gloss value and viscosity of the coating film were measured.

Examples 2 to 4 and Comparative Example 2
Instead of using (C-1) of Example 1, (C-2) to (C-4) and (I-2) were used, respectively, to prepare a pigment dispersion as in Example 1.

Examples 5 and 6 and Comparative Example 1
Copper phthalocyanine pigment (CIPigument Blue 15: 3), pigment dispersant (C-5) obtained in Production Examples 5 and 6, (C-6) or pigment dispersant obtained in Comparative Production Example 1 (I-1 ) Were each weighed in 20 parts of a 30% solution, 42 parts of toluene, 18 parts of isopropyl alcohol, and 300 parts of steel beads, and a pigment dispersion was prepared in the same manner as in Example 1.

Comparative Example 3
Copper phthalocyanine pigment (CIPigument Blue 15: 3), 6 parts of pigment dispersant (I-3) obtained in Production Comparative Example 5, 74 parts of xylene, and 300 parts of steel beads were weighed. A dispersion was created.

Comparative Example 4
20 parts of copper phthalocyanine pigment (CIPigument Blue 15: 3), 6 parts of pigment dispersant (I-4) obtained in Production Comparative Example 6, 37 parts of xylene, 37 parts of butyl cellosolve acetate, and 300 parts of steel beads were weighed. A pigment dispersion was prepared in the same manner as in Example 1.

Examples 7-12 and Comparative Examples 5-8
In place of the copper phthalocyanine pigment used in Examples 1 to 6 and Comparative Examples 1 to 4, an azo lake pigment (CIPigument Red 48: 3) was used, and a pigment dispersion was similarly prepared.

Examples 13-18 and Comparative Examples 9-12
Instead of the copper phthalocyanine pigment used in Examples 1 to 6 and Comparative Examples 1 to 4, a disazo yellow pigment (CIPigument Yellow 14) was used, and a pigment dispersion was similarly prepared.

Examples 19-24 and Comparative Examples 13-16
In place of the copper phthalocyanine pigment used in Examples 1 to 6 and Comparative Examples 1 to 4, a carbon pigment (CIPigument Black 7) was used, and a pigment dispersion was similarly prepared.

<60 degree gloss value>
The pigment dispersion obtained in each example was applied onto a PET film using a bar coater (No. 6), dried, and then subjected to JIS K 5600-4-7 “Paint General Test Method”. In accordance with Section 7 “Specular Gloss”, the 60-degree gloss value of the coating film was measured using a specular gloss meter (manufactured by Nippon Denshoku Industries Co., Ltd.).
<Viscosity>
The viscosity was measured with a BL type rotational viscometer (manufactured by Toki Sangyo Co., Ltd.) at 20 ° C. using a No. 1, No. 2 or No. 3 rotor.

Table 1 shows the performance evaluation test results obtained in each example and comparative example.

The evaluation results show that the higher the gloss value and the lower the viscosity, the better the pigment dispersibility. As is apparent from the above, the pigment dispersant of the present invention is a printing ink that is superior in pigment dispersibility compared to the comparative example. Can be provided.

The pigment dispersant of the present invention can be used in any application in which pigments such as printing ink, paint, colorant, inkjet ink, color toner, and color filter resist are dispersed.

Claims (8)

A graft polymer (C) comprising a main chain (A) and a side chain (B), wherein the main chain (A) comprises an amino group, an imino group and a monovalent or divalent aromatic hydrocarbon group. A graft polymer comprising a polyurethane resin (a1) and / or a polyurea resin (a2) having at least one selected from the above, and a side chain (B) comprising a polyether skeleton (b1) and / or a polyester skeleton (b2). A pigment dispersant for printing ink, comprising: The pigment dispersant for printing ink according to claim 1, wherein the number average molecular weight of the main chain (A) is 500 to 500,000. The pigment dispersant for printing ink according to claim 1 or 2, wherein the number average molecular weight of one side chain (B) is 500 to 100,000. The pigment dispersant for printing ink according to any one of claims 1 to 3, wherein the content of the aromatic ring in the main chain (A) is 10 to 90% by weight. The pigment dispersant for printing ink according to any one of claims 1 to 4, wherein the amine value in the main chain (A) is 1-1000. The pigment dispersant for printing ink according to any one of claims 1 to 5, wherein the amino group in the main chain (A) is a tertiary amino group. A diamino compound (D) comprising n imino groups represented by the following general formula (1) and a polyether skeleton (b1) or a polyester skeleton (b2), and an organic isocyanate compound having two isocyanate groups in the molecule A pigment dispersant for printing ink, comprising a polymer (F) obtained by reacting (E).
(In the formula, R ₁ and R ₂ each independently represent a linear or branched alkyl group having 1 to 10 carbon atoms, and X ₁ represents either a polyether skeleton (b1) or a polyester skeleton (b2). n represents an integer of 1 to 4.) A printing ink composition comprising the pigment dispersant according to claim 1.