JP2009233486A - Method of manufacturing pigment dispersant, curable composition, curable ink composition, ink composition for inkjet, and inkjet recording method - Google Patents

Abstract

Provided is a method for producing a pigment dispersant excellent in dispersibility and dispersion stability of fine pigments, and a pigment dispersion composition having a clear color tone and high coloring power, having high sensitivity and blocking resistance. An ink jet curable composition and an ink jet recording method are provided.
A method for producing a pigment dispersant in which at least the following (a), (b), and (c) are reacted in (d) a polymerizable compound.
(A) a compound having a hydroxyl group and a pigment-adsorptive partial structure;
(B) a polymer selected from aliphatic polyester, poly (meth) acrylate, and polyether, and having a hydroxyl group or a primary amino group;
(C) Bifunctional or higher isocyanate compounds.
[Selection figure] None

Description

  The present invention relates to a method for producing a pigment dispersant that can stably finely disperse a pigment that is a coloring component of a curable composition, and further has good dispersibility of the pigment, excellent storage stability, and imparted energy. The present invention relates to a curable composition having excellent curability. Furthermore, the present invention relates to an ink composition suitable for ink jet capable of forming a high quality image using the ink composition and an ink jet recording method using the ink composition.

As an image recording method for forming an image on a recording medium such as paper or a plastic sheet based on an image data signal, there are an electrophotographic method, a sublimation type and a melt type thermal transfer method, an ink jet method and the like. In particular, the ink jet method can be implemented with an inexpensive apparatus, and the ink can be efficiently used because the ink is ejected only on the required image portion to form the image directly on the recording medium. Cost is low. Furthermore, it is excellent in that a high-definition image can be recorded by ejecting very fine droplets with less noise.
According to the inkjet method, printing is possible not only on plain paper but also on non-liquid-absorbing recording media such as plastic sheets and metal plates. However, high speed and high image quality when printing are important issues. In addition, the time required for drying and curing the droplets after printing has a property of greatly affecting the sharpness of the image.

As one of the ink jet methods, there is a recording method using an ink for ink jet recording that can be cured by irradiation with actinic radiation. According to this method, a sharp image can be formed by irradiating with radiation immediately after printing and curing the ink droplets.
Such a curable inkjet ink composition is required to have high pigment dispersibility and stability over time in order to form a high-definition image excellent in color developability and to discharge ink stably. In order to impart a clear color tone and high coloring power to the ink composition, it is essential to make the pigment finer. In particular, in the ink used for inkjet recording, since the ejected ink droplets have a great influence on the sharpness of the image, the ejected droplets are also small, and the thickness of the ink cured film formed from the ink It is essential to use finer particles. As described above, when the pigment particles are further miniaturized in order to obtain a high coloring power, it becomes difficult to disperse the pigment fine particles, and aggregates are easily generated. Moreover, the problem that the viscosity of a composition rises by addition of a dispersing agent also arises. The occurrence of pigment aggregates and the increase in viscosity of the ink composition both have an adverse effect on the ink ejection properties. Therefore, it is not preferable to use an ink composition in which pigment aggregation or thickening has occurred for inkjet recording.

Moreover, when using an ink composition for inkjet recording, it must be excellent in heat cycle property. The ink composition is stored in a cartridge and heated to reduce the liquid viscosity during ejection, but the temperature is lowered during non-ejection and storage, and thus undergoes repeated heating-cooling temperature changes. This temperature change also has an adverse effect on the pigment dispersibility, resulting in a problem that the dispersibility of the pigment decreases with time, and the aggregation and thickening of the pigment tend to occur.
In the curable inkjet ink, curability for forming a sharp image and film physical properties after curing are also important factors. In curable ink-jet inks, the sharpness of the image is ensured by rapid curing by irradiation, so pigment dispersants that inhibit curing and pigment dispersants that contain solvents that are non-curing components have reduced curability. Cause bleeding and reduced productivity. In a curable inkjet ink containing a solvent that is a non-curable component, a decrease in curing sensitivity due to the plastic effect, concentration change during storage due to volatilization of the solvent component, ejection failure, There is a problem in that various defects such as so-called blocking that the recording medium adheres and the printed surface of the recorded matter and the recording medium are soiled occur.

Accordingly, there is a need for an ink composition that has sufficient fluidity, stably disperses a finely divided pigment, and is excellent in curability. Various proposals have been made on dispersants for obtaining stable pigment dispersions.
For example, an ink composition containing a dispersing agent such as poly (ethyleneimine) -poly (12-hydroxystearic acid) graft polymer and a specific monomer for dissolving the dispersing agent and not using an organic solvent (see Patent Document 1) ), A non-aqueous pigment dispersion composition using a graft copolymer using a nitrogen atom-containing vinyl polymerizable macromonomer (see Patent Document 2), N-vinylamide, N-vinyllactam, vinyl or allyl-substituted nitrogen A polyurethane dispersant having a polymer containing a heterocyclic ring and another type of polymer as a graft chain (see Reference 3) has been proposed. Using these pigment dispersants and ink compositions can surely disperse the pigments finer, and the stability of the ink will be higher than before, but the curable composition without distilling off the solvent of the dispersant synthesized in the organic solvent. When used for products, there was still room for improvement in curing sensitivity and blocking resistance.
JP 2004-131589 A JP 2007-277506 A Special Table 2002-526254

The present invention is intended to provide a method for producing a pigment dispersant which is excellent in the dispersibility and dispersion stability of fine pigments and is excellent in the production suitability of a pigment dispersion composition. Moreover, the further objective of this invention is providing the pigment dispersion composition which has a clear color tone and high coloring power by using the pigment dispersant obtained by the said manufacturing method.
Furthermore, the present invention can form a high-quality image, has high sensitivity due to irradiation with actinic radiation, and even if the printed matter is stored in an overlapping manner, the printed surface and the printed surface, or the printed surface and the substrate, It is an object of the present invention to provide a curable composition suitable for inkjet recording that does not cause so-called blocking, and to provide a curable ink composition using the curable composition and an inkjet recording method.

As a result of intensive studies, the present inventors have achieved excellent pigment dispersibility by a method of synthesizing a specific compound as a pigment dispersant in a polymerizable compound, and have undergone long-term storage or repeated temperature changes. A pigment dispersant in which a decrease in dispersion stability is effectively suppressed even after is obtained, and by using the pigment dispersant, a curable composition excellent in curability and a curable ink composition are obtained. As a result, the present invention was completed.
Means for solving the above problems are as follows.

<1> A method for producing a pigment dispersant in which at least the following (a), (b), and (c) are reacted in a polymerizable compound (d).
(A) a compound having a hydroxyl group and a pigment-adsorptive partial structure;
(B) a polymer selected from aliphatic polyester, poly (meth) acrylate, and polyether, and having a hydroxyl group or a primary amino group;
(C) Bifunctional or higher isocyanate compounds.

<2> The compound (a) having a hydroxyl group and a pigment-adsorptive partial structure is a polymer having a number average molecular weight in the range of 500 to 5,000, and (b) the aliphatic polyester or poly (meta). The number average molecular weight of the polymer selected from acrylates and polyethers and having a hydroxyl group or primary amino group is in the range of 350 to 15000, and is included in one molecule of the (c) bifunctional or higher functional isocyanate compound. The manufacturing method of the pigment dispersant as described in <1> which has 2-6 isocyanate groups.
<3> The pigment adsorbing partial structure in the compound (a) having a hydroxyl group and a pigment adsorbing partial structure is a carboxyl group, carboxylate, secondary amino group, tertiary amino group, amide bond, urea. The method for producing a pigment dispersant according to <1> or <2>, which is at least one selected from a bond, a urethane bond, a carbonate bond, and an imide bond.

<4> A polymer in which the compound (a) having a hydroxyl group and a pigment-adsorptive partial structure is selected from polyamide, polyurethane, polyurea, and poly (meth) acrylamides, and having a hydroxyl group at the terminal; <1> to <1 which is a compound comprising any one of a vinyl polymer obtained by reacting (meth) acrylate; and a vinyl polymer obtained by reacting carboxylic acid-containing (meth) acrylate. The manufacturing method of the pigment dispersant of any one of 3>.
<5> selected from (a) a hydroxyl group and a hydroxyl group contained in a compound having a pigment-adsorptive partial structure, and (b) an aliphatic polyester, poly (meth) acrylate, and polyether; The pigment dispersion according to any one of <1> to <4>, wherein the number of hydroxyl groups or primary amino groups contained in the polymer having a primary amino group is 1 to 2 per molecule, respectively. Manufacturing method.
<6> The method for producing a pigment dispersant according to any one of <1> to <5>, wherein the polymerizable compound (d) is an isocyanate non-reactive (meth) acrylate or vinyl ether.

<7> The method for producing a pigment dispersant according to any one of <1> to <5>, wherein the polymerizable compound (d) is a compound having an isocyanate non-reactive oxetanyl group.
<8> A pigment dispersion composition comprising a pigment dispersant and a pigment produced by the production method according to any one of <1> to <7>.
<9> A curable composition containing the pigment dispersion composition according to <8>.
<10> The curable composition according to <9>, further comprising a polymerization initiator.
<11> A curable ink composition containing the curable composition according to <9> or <10>.
<12> The curable ink composition according to <11>, which is for inkjet recording.
<13> An ink jet recording method using the curable ink composition according to <12>.

The pigment dispersant obtained by the production method of the present invention is a polyaddition reaction product of two or more kinds of compounds having a hydroxyl group or a primary amino group at a terminal and a polyfunctional isocyanate compound, and a pigment adsorbing graft chain and A so-called graft copolymer having a medium affinity graft chain (hereinafter also referred to as a specific polymer).
This specific polymer is obtained by reacting the pigment-adsorptive functional group contained in the compound (a) with the hydroxyl group or primary amino group contained in the compounds (a) and (b) with the isocyanate group of the compound (c). It is thought that it is strongly adsorbed to the pigment by the polyurethane backbone that is formed.
Furthermore, the dispersion medium in the pigment dispersion composition and the aliphatic polyester, poly (meth) acrylate and polyether derived from the polymer (b) having a high affinity with the polymerizable compound or solvent in the curable composition are selected. It is presumed that the steric repulsion action of the graft chain suppresses aggregation of the pigments and enables stable dispersion.

  ADVANTAGE OF THE INVENTION According to this invention, the method of manufacturing the pigment dispersant excellent in the dispersibility of a fine pigment and dispersion stability can be provided. In addition, a pigment dispersion composition having a clear color tone and high coloring power can be provided, and a high-quality image can be formed. Since the pigment dispersant produced by the production method of the present invention uses the polymerizable compound (d) as a reaction solvent, the non-curable organic solvent can be used without passing through a special step of removing the non-curable organic solvent. Can be produced. For this reason, if the dispersant produced by the production method of the present invention is used, the sensitivity by irradiation with actinic radiation is high, and the printed surface and the printed surface or the printed surface and the base material are stored even when the printed matter is stored repeatedly. A curable composition suitable for inkjet recording that does not cause so-called blocking that adheres to each other can be provided, and a curable ink composition using the curable composition and an inkjet recording method can be provided.

The present invention is a method for producing a pigment dispersant, characterized in that the following components (a), (b), and (c) are reacted not in a solvent but in (d) a polymerizable compound. To do.
(A) Compound having hydroxyl group and pigment-adsorptive partial structure (b) Polymer (c) 2 selected from aliphatic polyester, poly (meth) acrylate, and polyether and having hydroxyl group or primary amino group Functional or higher isocyanate compound The polymer obtained by the production method of the present invention (hereinafter, appropriately referred to as a specific polymer) has an excellent function as a pigment dispersant. When the pigment is dispersed using the specific polymer of the present invention, the pigment is finely and stably dispersed. In the present specification, when referring to both “acrylate” and “methacrylate” or any one of them, “(meth) acrylate” and both “acryl” and “methacryl” or any one of them are referred to as “( And (meth) acryl ”.

<(A) Compound having hydroxyl group and pigment adsorptive partial structure>
(A) A compound having a hydroxyl group and a pigment-adsorptive partial structure (hereinafter, appropriately referred to as (a) compound) interacts with the hydroxyl group that reacts with the isocyanate compound to form a urethane bond, and the pigment. It has a pigment adsorbing partial structure as an essential component.
(A) The hydroxyl group contained in a compound should just be a thing which can react with an isocyanate group, and can use both an aliphatic hydroxyl group and an aromatic hydroxyl group, but an aliphatic hydroxyl group is used preferably.
The number of hydroxyl groups is preferably 1 to 4 in one molecule, more preferably 1 to 2, and most preferably 2. When the number of hydroxyl groups is 5 or more, the solubility of the obtained pigment dispersant tends to decrease.

Further, when the compound (a) having one hydroxyl group per molecule is used, a pigment dispersant in which the compound (a) is introduced only at the terminal of the polymer is obtained, and when the compound (a) having two hydroxyl groups is used. A pigment dispersant into which a plurality of compounds (a) are introduced is obtained. (A) When the number of pigment-adsorptive functional groups contained in the compound is increased, the adsorptivity to the pigment is enhanced. Therefore, a graft copolymer can be obtained using the compound (a) having two hydroxyl groups introduced. Most preferred.
In view of adjusting the molecular weight, it is also preferable to use a compound (a) having one hydroxyl group and a polymer (b) having two hydroxyl groups.

The compound (a) preferably has a plurality of pigment-adsorptive functional groups in the molecule in order to enhance the adsorptivity, and more preferably a polymer having a pigment-adsorptive functional group as a repeating unit.
(A) As for the number average molecular weight of a compound, 150-10000 are preferable, More preferably, it is 500-5000, 1000-5000 are the most preferable. If the molecular weight is too small, the side chains of the polymer produced will be short, and the adsorption capacity to the pigment will tend to decrease, and if the molecular weight is larger than this range, crosslinking between the pigment particles will be induced. As a result, a fine pigment dispersion cannot be obtained.

  (A) The pigment-adsorptive partial structure contained in the compound refers to a partial structure that can interact and adsorb on the pigment surface. The adsorption interaction can be selected according to the pigment type, the pigment surface treatment agent, and the surface state of the pigment, for example, acid-base interaction, hydrogen bond, π-π interaction, dipole-dipole interaction. Action, hydrophilicity / hydrophobic interaction and the like. As the pigment adsorbing partial structure, any structure can be used as long as it has the above-described interaction and does not react with an isocyanate group. In the present invention, a carboxyl group or a salt thereof, a secondary amino group, 1 A secondary amino group, an amide bond, a urea bond, a urethane bond, a carbonate bond, and an imide bond are preferable. Among these, a secondary amino group, a tertiary amino group, an amide bond, a urea bond, and an imide bond are included. Things are more preferable.

  The pigment-adsorptive partial structure is preferably introduced as a repeating unit in the compound (a), and the compound (a) is a polyamide, polyurea, polyurethane, polyimide having 1 to 4 hydroxyl groups at the terminal or It is preferably a homopolymer or a copolymer of (meth) acrylamides, nitrogen-containing (meth) acrylates, and carboxyl-containing (meth) acrylates. Among these, alkyl-substituted amino group-containing poly (meth) acrylamide, alkyl-substituted amino group-containing (meth) acrylate, urethane bond-containing (meth) acrylate, amide bond-containing poly (meth) acrylate, urea bond-containing poly (meth) acrylate , Preferably carboxyl-containing (meth) acrylate, alkyl-substituted amino group-containing polyalkyl (meth) acrylamide, alkyl-substituted amino group-containing (meth) acrylate, urethane bond-containing (meth) acrylate, amide bond-containing poly (meta) ) Acrylate and urea bond-containing poly (meth) acrylate are more preferred.

As a method for synthesizing the poly (meth) acrylate or poly (meth) acrylamide having a hydroxyl group at the chain end, for example, radical polymerization of a corresponding vinyl monomer using a thiol having a desired number of hydroxyl groups as a chain transfer agent. It can be easily synthesized.
Although the example of the chain transfer agent used suitably for this invention is shown below, if the polymer made into the objective of this invention is obtained, there will be no limitation and it can use. For example, chain transfer agents capable of introducing one hydroxyl group at the chain end include 2-mercapto-1-ethanol, 3-mercapto-1-propanol, 3-mercapto-3-methylbutan-1-ol, 6-mercapto-1- Examples include hexanol and 11-mercapto-1-undecanol.
Examples of the chain transfer agent capable of introducing two hydroxyl groups at the chain end include 1-thioglycerol.

In the present invention, an embodiment having one or two hydroxyl groups at the center of the chain is also preferably used. When one or two hydroxyl groups are introduced at the center of the chain, (c) two graft chains can be introduced by reaction with the isocyanate compound, and the same effect as when hydroxyl groups are introduced at the chain ends can be obtained. .
As a chain transfer agent capable of introducing one hydroxyl group into the chain center, 2,3-dimercapto-1-propanol is exemplified. As a chain transfer agent capable of introducing two hydroxyl groups into the chain center, 1,4-dithioerythritol is exemplified. .

The compound (a) can be easily obtained by polymerizing the nitrogen-containing vinyl monomer in the presence of these chain transfer agents. The nitrogen-containing vinyl monomer used in the present invention includes alkyl (meth) acrylamide, alkyl-substituted amino group-containing (meth) acrylamide, alkyl-substituted amino group-containing (meth) acrylate, urethane bond-containing (meth) acrylate, amide bond-containing poly (Meth) acrylate, urea bond-containing poly (meth) acrylate, vinylformamide, N-vinyllactam, N-vinylpyrrolidone, N-vinylcarbazole, 2-vinylpyridine, 4-vinylpyridine, allylamine and the like.
Among these, alkyl (meth) acrylamide, alkyl-substituted amino group-containing alkyl (meth) acrylamide, alkyl-substituted amino group-containing (meth) acrylate, urethane bond-containing (meth) acrylate, amide bond-containing (meth) acrylate, urea bond-containing poly (Meth) acrylate is preferably used.

  Below, the specific example of the nitrogen-containing vinyl monomer used suitably for this invention is shown. Examples of the alkyl (meth) acrylamide include N, N-dimethyl (meth) acrylamide, N-tert butyl acrylamide, Nn butyl acrylamide, and N-tert octyl acrylamide. Examples of the alkyl-substituted amino group-containing alkyl (meth) acrylamide include N-3-dimethylaminopropyl (meth) acrylamide. Examples of the alkyl-substituted amino group-containing (meth) acrylate include N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N- and tertbutylaminoethyl (meth) acrylate. Examples of the urethane bond-containing (meth) acrylate include n-butylcarbamoylethyl (meth) acrylate. Examples of the urea bond-containing poly (meth) acrylate include n-butylureidoethyl (meth) acrylate, N- (2-methacryloyloxyethyl) ethyleneurea, imidazolone ethyl (meth) acrylate, and the like.

  Examples of the carboxyl-containing group (meth) acrylate include (meth) acrylic acid, carboxyethyl (meth) acrylate, mono-2- (methacryloyloxy) ethyl (meth) acrylate, and mono-2-[(meth) acryloyloxy]. Examples thereof include ethyl succinate, mono-2-[(meth) acryloyloxy] ethyl phthalate, and mono-2-[(meth) acryloyloxy] ethyl hexahydrophthalate.

Specific examples of preferable compounds are given below as the compound (a).
In the following formula, n is an integer in the range of 3-50.

<(B) Polymer selected from aliphatic polyester, poly (meth) acrylate, and polyether and having a hydroxyl group or a primary amino group>
(B) a polymer selected from aliphatic polyester, poly (meth) acrylate, and polyether, having a hydroxyl group or primary amino group reacts with the isocyanate of (c) to form a hydroxyl group and a urea bond that form a urethane bond. A polymer component capable of imparting affinity between the primary amino group to be generated and the pigment and the medium is included as an essential component.

Aliphatic polyester, poly (meth) acrylate, and polyether, which are components for imparting affinity with the medium, are selected according to the affinity with the solvent, and any one having good affinity is used. it can.
Aliphatic polyesters can be synthesized by ring-opening polymerization. For example, aliphatic polyesters having different solvent affinity can be synthesized by copolymerizing different monomers such as ε-caprolactone, γ-butyrolactone, and valerolactone. it can.

The polyether is obtained by ring-opening polymerization of a cyclic ether such as ethylene oxide, propylene oxide, oxetane compound or tetrahydrofuran, and can be adjusted to have an affinity suitable for the medium by copolymerizing different cyclic ethers.
Poly (meth) acrylate can be easily synthesized by polymerizing (meth) acrylate. As the ester substituent of poly (meth) acrylate, an alkyl group having 1 to 20 carbon atoms or an aryl group which may be substituted is preferably used. Examples of the substituent of the alkyl group include a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an aryl group, an alkoxy group, a glycidyl group, and an alkenyl group, and an alkyl group substituted with a hydroxyl group, an aryl group, and an alkoxy group, and An unsubstituted alkyl group is preferably used. Substitution with a group having strong pigment affinity is not preferable because it is adsorbed on the pigment and cannot exhibit a sufficient steric repulsion effect.

Specific examples of preferred compounds as (b) are given below.
In the following formula, m is an integer in the range of 10 to 150, p is 1 to 149, q is 1 to 149, and p + q is an integer in the range of 10 to 150.

  (B) The number average molecular weight of the polymer is preferably 350 to 15000. More preferably, it is 500-12000, and 1000-10000 are the most preferable. If the molecular weight is too small, the steric repulsion effect tends to be small, and the dispersibility of the pigment tends to decrease. On the other hand, if the molecular weight is larger than this range, the viscosity of the dispersant is increased, which is not preferable.

<(C) Bifunctional or higher isocyanate compound>
(C) As the bifunctional or higher functional isocyanate compound, a compound having 2 to 6 isocyanate groups in one molecule is preferably used. Examples of the compound having 2 to 6 isocyanate groups include organic polyisocyanate.
As the organic polyisocyanate, any conventionally known one can be used, but aromatic diisocyanates such as 4,4′-diphenylmethane diisocyanate (MDI), 2,4- or 2,6-tolylene diisocyanate (TDI), m- or p-phenylene diisocyanate, 1,3- or 1,4-xylylene diisocyanate (XDI), 1,5-naphthalene diisocyanate (NDI), 3,3'-dimethyl-4,4'-biphenylene diisocyanate (TODI) ) And the like, for example, hexamethylene diisocyanate (HDI), hydrogenated MDI (H12MDI), isophorone diisocyanate (IPDI) and the like. Prepolymer-type, nurate-type, urea-type carbodiimide-type modified products of these diisocyanates are also preferable. A mixture of two or more of these isocyanate compounds or modified products can also be used.

<Method for producing specific polymer>
For production of the specific polymer of the present invention, a chain extender can be used as necessary. As the chain extender, any conventionally known one can be used, but low molecular weight polyols such as ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol, 1,6-hexanediol, trimethylolpropane, neo Pentyl glycol, hydroquinone, bis (hydroxyethyl) benzene, 2,2'- or 4,4'-dihydroxydiphenylmethane, 2,2-bis (4-hydroxyphenyl) propane, or low molecular weight diamines such as ethylenediamine and propylene Diamine, m- or p-phenylenediamine, 1,3- or 1,4-xylylenediamine, isophoronediamine and the like can be used.

  The ratio of the (a) compound, (b) polymer, and (c) isocyanate compound used in the production of the specific polymer of the present invention is the mass of the specific polymer, and (a) 2 to 50% (B) 50 to 93%, (c) preferably 0.5 to 12%, (a) 3 to 45%, (b) 55 to 90%, (c) 1 to 10% The range is more preferable, and the range of (a) 5 to 35%, (b) 60 to 90%, and (c) 1 to 8% is most preferable.

The number average molecular weight of the specific polymer of the present invention is preferably in the range of 3000 to 150,000, more preferably 4000 to 120,000, and most preferably in the range of 6000 to 100,000. When the molecular weight is smaller than this range, the dispersion stability is lowered. When the molecular weight is larger than this range, the viscosity of the dispersion tends to increase.
Specific examples of the specific dispersant used in the present invention [Exemplary compounds (P-1) to (P-6)] are shown below, but the present invention is not limited thereto. In addition, these graft polymers which are the specific dispersants of the present invention are synthesized using the raw material components described in Table 1 below at the charging ratios described.

<(D) Polymerizable compound>
The specific polymer of the present invention is produced by reacting (a) a compound, (b) a polymer, and (c) an isocyanate compound in (d) a polymerizable compound. Generally, a polyurethane compound is produced by reacting a compound having a hydroxyl group such as (a) a compound or (b) a polymer with an isocyanate compound in an organic solvent or without a solvent.
In the curable composition in which the pigment dispersant which is the specific polymer of the present invention is suitably used, the organic solvent causes a decrease in curability, plasticization of the cured film, and blocking, so that the non-curable component It is preferable to remove as much as possible the organic solvent. However, in these methods, it is difficult to synthesize polyurethane with a high softening point when the reaction is carried out in the absence of a solvent, and the reaction in an organic solvent removes the organic solvent in order to remove the solvent by warm distillation or vacuum distillation. It was necessary to provide a separate process such as reprecipitation.

  In the present invention, since the polymerizable compound (d) is used as the reaction solvent, when the specific polymer of the present invention is used in the curable composition, the reaction solvent reacts with other curable compositions, and the curable composition and film quality are reduced. Decline can be prevented.

  As such (d) polymerizable compound, various polymerizable compounds such as radical polymerizable compounds, cationic polymerizable compounds and anionic polymerizable compounds may be used in the curable composition as long as they do not react with isocyanate groups. It can select according to the kind of polymerization initiator. One or more polymerizable compounds can be used in combination for the purpose of adjusting the reaction rate, ink physical properties, cured film physical properties, pigment dispersion stability, and the like. The polymerizable compound may be a monofunctional compound or a polyfunctional compound.

As the polymerization solvent in the production method of the present invention, one type of polymerizable compound may be used or two or more types may be used in combination. In addition, a pigment dispersion is prepared using the specific polymer produced by the production method of the present invention as a pigment dispersant, and the pigment dispersion is further cured with a polymerization initiator, a polymerizable compound, a polymerizable oligomer, and the like. In the case of preparing a curable composition by adding a functional component, the polymerizable compound newly added to prepare the curable composition may have a functional group capable of reacting with an isocyanate such as a hydroxyl group. good.
Specific examples of the polymerizable compound that can be suitably used in the present invention are shown below, but the present invention is not limited thereto.

In the present invention, as the polymerizable compound (d), various known radical polymerizable monomers that cause a polymerization reaction with an initiation species generated from a photo radical initiator can be used.
Examples of the radical polymerizable monomer include (meth) acrylates, (meth) acrylamides, vinyl ethers, aromatic vinyls, and the like.
Examples of the (meth) acrylates used as the radical polymerizable monomer include monofunctional (meth) acrylate, bifunctional (meth) acrylate, trifunctional (meth) acrylate, tetrafunctional (meth) acrylate, and five Functional (meth) acrylates, hexafunctional (meth) acrylates, and the like can be given.

  Examples of the monofunctional (meth) acrylate include hexyl group (meth) acrylate, 2-ethylhexyl (meth) acrylate, tert-octyl (meth) acrylate, isoamyl (meth) acrylate, decyl (meth) acrylate, and isodecyl (meth). Acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, cyclohexyl (meth) acrylate, 4-n-butylcyclohexyl (meth) acrylate, bornyl (meth) acrylate, isobornyl (meth) acrylate, benzyl (meth) acrylate, 2-ethylhexyl diglycol (meth) acrylate, butoxyethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 4-bromobutyl (meth) acrylate, cyanoe (Meth) acrylate, benzyl (meth) acrylate, butoxymethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, alkoxymethyl (meth) acrylate, alkoxyethyl (meth) acrylate, 2- (2-methoxyethoxy) ethyl (Meth) acrylate, 2- (2-butoxyethoxy) ethyl (meth) acrylate, 2,2,2-tetrafluoroethyl (meth) acrylate, 1H, 1H, 2H, 2H perfluorodecyl (meth) acrylate, 4- Butylphenyl (meth) acrylate, phenyl (meth) acrylate, 2,4,5-tetramethylphenyl (meth) acrylate, 4-chlorophenyl (meth) acrylate, phenoxymethyl (meth) acrylate, phenoxyethyl (meth) acrylate, Ricidyl (meth) acrylate, glycidyloxybutyl (meth) acrylate, glycidyloxyethyl (meth) acrylate, glycidyloxypropyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylamino Ethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, diethylaminopropyl (meth) acrylate, trimethylsilylpropyl (meth) acrylate, polyethylene oxide monomethyl ether (meth) acrylate, oligoethylene oxide monomethyl ether (meth) acrylate, polyethylene oxide monoalkyl Ether (meth) acrylate, dipropylene glycol (meth) acrylate, polypropylene Sid monoalkyl ether (meth) acrylate, oligopropylene oxide monoalkyl ether (meth) acrylate, butoxydiethylene glycol (meth) acrylate, trifluoroethyl (meth) acrylate, EO modified phenol (meth) acrylate, EO modified cresol (meth) acrylate , EO-modified nonylphenol (meth) acrylate, PO-modified nonylphenol (meth) acrylate, EO-modified-2-ethylhexyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dicyclopentanyl (Meth) acrylate, (3-ethyl-3-oxetanylmethyl) (meth) acrylate, phenoxyethylene glycol (meth) acrylate It is.

  Examples of the bifunctional (meth) acrylate include 1,6-hexanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and 2,4-dimethyl. -1,5-pentanediol di (meth) acrylate, butylethylpropanediol (meth) acrylate, ethoxylated cyclohexanemethanol di (meth) acrylate, polyethylene glycol di (meth) acrylate, oligoethylene glycol di (meth) acrylate, Ethylene glycol di (meth) acrylate, 2-ethyl-2-butyl-butanediol di (meth) acrylate, EO-modified bisphenol A di (meth) acrylate, bisphenol F polyethoxydi (meth) acrylate, polyp Pyrene glycol di (meth) acrylate, oligopropylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 2-ethyl-2-butylpropanediol di (meth) acrylate, 1,9-nonane ( Examples include meth) acrylate, propoxylated ethoxylated bisphenol A di (meth) acrylate, tricyclodecane di (meth) acrylate, dipropylene glycol di (meth) acrylate, propoxylated neopentyl glycol di (meth) acrylate, and the like.

  Examples of the trifunctional (meth) acrylate include trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, trimethylolpropane alkylene oxide-modified tri (meth) acrylate, trimethylolpropane tri ((meta ) Acryloyloxypropyl) ether, isocyanuric acid alkylene oxide modified tri (meth) acrylate, dipentaerythritol tri (meth) acrylate propionate, tri ((meth) acryloyloxyethyl) isocyanurate, propoxylated trimethylolpropane tri (meth) Examples thereof include acrylate and ethoxylated glycerin triacrylate.

Examples of the tetrafunctional (meth) acrylate include pentaerythritol tetra (meth) acrylate, sorbitol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate propionate, and ethoxylated penta Examples include erythritol tetra (meth) acrylate.
Examples of pentafunctional (meth) acrylates include sorbitol penta (meth) acrylate and dipentaerythritol penta (meth) acrylate.
Examples of hexafunctional (meth) acrylates include dipentaerythritol hexa (meth) acrylate, sorbitol hexa (meth) acrylate, phosphazene alkylene oxide-modified hexa (meth) acrylate, and ε-captolactone-modified dipentaerythritol hexa (meth). ) Acrylate and the like.

  Examples of (meth) acrylamides used as the radical polymerizable monomer include (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-propyl (meth) acrylamide, and N-n. -Butyl (meth) acrylamide, Nt-butyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-methylol (meth) acrylamide, N, N-dimethyl (meth) Examples include acrylamide, N, N-diethyl (meth) acrylamide, and (meth) acryloylmorpholine.

  Examples of the aromatic vinyl used as the radical polymerizable monomer include styrene, methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, isopropyl styrene, chloromethyl styrene, methoxy styrene, acetoxy styrene, chloro styrene, dichloro styrene. , Bromostyrene, vinyl benzoic acid methyl ester, 3-methylstyrene, 4-methylstyrene, 3-ethylstyrene, 4-ethylstyrene, 3-propylstyrene, 4-propylstyrene, 3-butylstyrene, 4-butylstyrene, 3-hexyl styrene, 4-hexyl styrene, 3-octyl styrene, 4-octyl styrene, 3- (2-ethylhexyl) styrene, 4- (2-ethylhexyl) styrene, allyl styrene, isoprop Rusuchiren, butenylstyrene, octenyl styrene, 4-t-butoxycarbonyl styrene, 4-methoxystyrene, and a 4-t-butoxystyrene.

  Examples of the monofunctional vinyl ether compound used as the radical polymerizable monomer include methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, n-butyl vinyl ether, t-butyl vinyl ether, 2-ethylhexyl vinyl ether, n-nonyl vinyl ether, lauryl vinyl ether, and cyclohexyl. Vinyl ether, cyclohexyl methyl vinyl ether, 4-methylcyclohexyl methyl vinyl ether, benzyl vinyl ether, dicyclopentenyl vinyl ether, 2-dicyclopentenoxyethyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, butoxyethyl vinyl ether, methoxyethoxyethyl vinyl ether, ethoxyethoxy Ethyl vinyl A Le, methoxy polyethylene glycol vinyl ether, tetrahydrofurfuryl vinyl ether, chloroethyl vinyl ether, chlorobutyl vinyl ether, phenylethyl vinyl ether, phenoxy polyethylene glycol vinyl ether.

Examples of the polyfunctional vinyl ether compound used as the radical polymerizable monomer include ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, polyethylene glycol divinyl ether, propylene glycol divinyl ether, butylene glycol divinyl ether, and hexane. Divinyl ethers such as diol divinyl ether, bisphenol A alkylene oxide divinyl ether, bisphenol F alkylene oxide divinyl ether; trimethylol ethane trivinyl ether, trimethylol propane trivinyl ether, ditrimethylol propane tetravinyl ether, glycerin trivinyl ether, pentaerythritol ether Lavinyl ether, dipentaerythritol pentavinyl ether, dipentaerythritol hexavinyl ether, ethylene oxide-added trimethylolpropane trivinyl ether, propylene oxide-added trimethylolpropane trivinyl ether, ethylene oxide-added ditrimethylolpropane tetravinyl ether, propylene oxide-added ditrimethylolpropane tetravinyl ether Polyfunctional vinyl ethers such as ethylene oxide-added pentaerythritol tetravinyl ether, propylene oxide-added pentaerythritol tetravinyl ether, ethylene oxide-added dipentaerythritol hexavinyl ether, propylene oxide-added dipentaerythritol hexavinyl ether And the like.
Of the polyfunctional vinyl ether compounds described above, di- or trivinyl ether compounds are preferable from the viewpoints of curability, adhesion to a recording medium, surface hardness of the formed image, and the like, and particularly divinyl ether compounds are more preferable. Since the vinyl ether compound mentioned above also has cationic polymerizability, it can be preferably used as a cationic polymerizable monomer described later.

  Furthermore, examples of the radical polymerizable monomer in the present invention include vinyl esters [vinyl acetate, vinyl propionate, vinyl versatate, etc.], allyl esters [allyl acetate, etc.], halogen-containing monomers [vinylidene chloride, chloride] Vinyl etc.], vinyl cyanide [(meth) acrylonitrile etc.], olefins [ethylene, propylene etc.] and the like.

  Of these, (d) polymerizable compounds in the present invention are preferably (meth) acrylates, (meth) acrylamides, and vinyl ethers from the viewpoints of curability and storage stability. From the viewpoint of the curing speed and the viscosity of the ink composition, it is preferable to use the above polyfunctional (meth) acrylate in combination with monofunctional or polyfunctional (meth) acrylate, vinyl ethers, and (meth) acrylamide.

  Examples of the cationic polymerizable monomer used as the polymerizable compound (d) in the present invention include, for example, JP-A-6-9714, JP-A-2001-31892, JP-A-2001-40068, and JP-A-2001-55507. , Epoxy compounds, vinyl ether compounds, oxetane compounds and the like described in each publication such as JP 2001-310938, 2001-310937, and 2001-220526. Among these, from the viewpoint of stability in the presence of isocyanate and adsorptive functional groups, vinyl ether compounds and oxetane compounds that are non-reactive with hydroxyl groups or adsorptive functional groups are preferably used. As a vinyl ether compound, the same vinyl ether compound as what was described as a radically polymerizable monomer can be used.

  The oxetane compound used as the cationic polymerizable monomer refers to a compound having an oxetane ring, and is described in JP-A Nos. 2001-220526, 2001-310937, and 2003-341217. As such, known oxetane compounds can be arbitrarily selected and used. The compound having an oxetane ring is preferably a compound having 1 to 4 oxetane rings in the structure. By using such a compound, it becomes easy to maintain the viscosity of the ink composition in a good handling property range, and it is possible to obtain high adhesion of the cured ink to the recording medium. .

  Examples of the monofunctional oxetane used as the cationic polymerizable monomer include, for example, 3- (meth) allyloxymethyl-3-ethyloxetane, (3-ethyl-3-oxetanylmethoxy) methylbenzene, 4-fluoro- [ 1- (3-ethyl-3-oxetanylmethoxy) methyl] benzene, 4-methoxy- [1- (3-ethyl-3-oxetanylmethoxy) methyl] benzene, [1- (3-ethyl-3-oxetanylmethoxy) Ethyl] phenyl ether, isobutoxymethyl (3-ethyl-3-oxetanylmethyl) ether, isobornyloxyethyl (3-ethyl-3-oxetanylmethyl) ether, isobornyl (3-ethyl-3-oxetanylmethyl) ether, 2-ethylhexyl (3-ethyl-3-oxetanylme ) Ether, ethyl diethylene glycol (3-ethyl-3-oxetanylmethyl) ether, dicyclopentadiene (3-ethyl-3-oxetanylmethyl) ether, dicyclopentenyloxyethyl (3-ethyl-3-oxetanylmethyl) ether, Dicyclopentenyl (3-ethyl-3-oxetanylmethyl) ether, tetrahydrofurfuryl (3-ethyl-3-oxetanylmethyl) ether, tetrabromophenyl (3-ethyl-3-oxetanylmethyl) ether, 2-tetrabromophenoxy Ethyl (3-ethyl-3-oxetanylmethyl) ether, tribromophenyl (3-ethyl-3-oxetanylmethyl) ether, 2-tribromophenoxyethyl (3-ethyl-3-oxetanylmethyl) ether, Xylethyl (3-ethyl-3-oxetanylmethyl) ether, pentachlorophenyl (3-ethyl-3-oxetanylmethyl) ether, pentabromophenyl (3-ethyl-3-oxetanylmethyl) ether, bornyl (3-ethyl-3- Oxetanylmethyl) ether and the like.

  Examples of the polyfunctional oxetane used as the cationic polymerizable monomer include, for example, 3,7-bis (3-oxetanyl) -5-oxa-nonane, 3,3 ′-(1,3- (2-methylenyl) Propanediylbis (oxymethylene)) bis- (3-ethyloxetane), 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, 1,2-bis [(3-ethyl-3- Oxetanylmethoxy) methyl] ethane, 1,3-bis [(3-ethyl-3-oxetanylmethoxy) methyl] propane, ethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, dicyclopentenylbis (3-ethyl) -3-oxetanylmethyl) ether, triethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether , Tetraethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, tricyclodecanediyldimethylene (3-ethyl-3-oxetanylmethyl) ether, trimethylolpropane tris (3-ethyl-3-oxetanylmethyl) ether 1,4-bis (3-ethyl-3-oxetanylmethoxy) butane, 1,6-bis (3-ethyl-3-oxetanylmethoxy) hexane, pentaerythritol tris (3-ethyl-3-oxetanylmethyl) ether, Pentaerythritol tetrakis (3-ethyl-3-oxetanylmethyl) ether, polyethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, dipentaerythritol hexakis (3-ethyl-3-oxetanylmethyl) ether, di Ntaerythritol pentakis (3-ethyl-3-oxetanylmethyl) ether, dipentaerythritoltetrakis (3-ethyl-3-oxetanylmethyl) ether, caprolactone-modified dipentaerythritol hexakis (3-ethyl-3-oxetanylmethyl) ether , Caprolactone-modified dipentaerythritol pentakis (3-ethyl-3-oxetanylmethyl) ether, ditrimethylolpropane tetrakis (3-ethyl-3-oxetanylmethyl) ether, EO-modified bisphenol A bis (3-ethyl-3-oxetanylmethyl) ) Ether, PO-modified bisphenol A bis (3-ethyl-3-oxetanylmethyl) ether, EO-modified hydrogenated bisphenol A bis (3-ethyl-3-oxetanylmethyl) ether, PO-modified hydrogenated bisphenol A bis (3-ethyl-3-oxetanylmethyl) ether, EO-modified bisphenol F (3-ethyl-3-oxetanylmethyl) ether, bis {[1-ethyl (3-oxetanyl)] methyl} ether Etc.

The compound having such an oxetane ring is described in detail in the aforementioned JP-A No. 2003-341217, paragraph numbers [0021] to [0084], and the compounds described herein can be suitably used in the present invention. .
Among the oxetane compounds as the cationic polymerizable monomer, it is preferable to use a compound having 1 to 2 oxetane rings from the viewpoint of viscosity and adhesiveness of the ink composition.

  In the present invention, after adjusting the pigment dispersion, a polymerizable compound other than (d) the polymerizable composition can be added in order to adjust the curable composition according to the application. In this case, a polymerizable monomer having a functional group that reacts with an isocyanate group or a hydroxyl group can be added to the polymerizable compound as long as the stability of the curable composition is not impaired.

  The cationic polymerizable monomer that can be added to the pigment dispersion to adjust the curable composition includes monofunctional or polyfunctional epoxy compounds. Examples of the monofunctional epoxy compound include phenyl glycidyl ether, p-tert-butylphenyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, allyl glycidyl ether, 1,2-butylene oxide, and 1,3-butadiene mono. Oxide, 1,2-epoxydodecane, epichlorohydrin, 1,2-epoxydecane, styrene oxide, cyclohexene oxide, 3-methacryloyloxymethylcyclohexene oxide, 3-acryloyloxymethylcyclohexene oxide, 3-vinylcyclohexene oxide, etc. Can be mentioned.

Examples of the polyfunctional epoxy compound include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether, brominated bisphenol A diglycidyl ether, brominated bisphenol F diglycidyl ether, and brominated bisphenol S. Diglycidyl ether, epoxy novolac resin, hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol F diglycidyl ether, hydrogenated bisphenol S diglycidyl ether, 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate 2- (3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxy) cyclohexane-meta-dioxane, bis (3,4-epoxycyclo Xylmethyl) adipate, vinylcyclohexene oxide, 4-vinylepoxycyclohexane, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, 3,4-epoxy-6-methylcyclohexyl-3 ′, 4′-epoxy-6 '-Methylcyclohexanecarboxylate, methylenebis (3,4-epoxycyclohexane), dicyclopentadiene diepoxide, ethylene glycol di (3,4-epoxycyclohexylmethyl) ether, ethylenebis (3,4-epoxycyclohexanecarboxylate) , Epoxyhexahydrophthalate dioctyl, epoxyhexahydrophthalate di-2-ethylhexyl, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether Glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ethers, 1,1,3-tetradecadiene dioxide, limonene dioxide, 1,2,7,8- Examples include diepoxyoctane and 1,2,5,6-diepoxycyclooctane.
Among these epoxy compounds, aromatic epoxides and alicyclic epoxides are preferable from the viewpoint of excellent curing speed, and alicyclic epoxides are more preferable.

  In the curable composition of the present invention, only one type of compound may be used as the cationic polymerizable monomer, or two or more types may be used in combination, but the viewpoint of effectively suppressing shrinkage during ink curing. Is preferably used in combination with at least one oxetane compound and at least one compound selected from an epoxy compound and a vinyl ether compound.

  When synthesizing the specific polymer of the present invention, a catalyst such as alkylamine, dibutyltin dilaurate, or bismuth triol may be added. The alkylamine may be added together with (a).

<Pigment dispersion>
By using the specific polymer produced by the production method of the present invention as a pigment dispersant, the pigment can be dispersed to prepare a pigment dispersion composition. In the pigment dispersion composition of the present invention, not only the pigment is stably and finely dispersed by the action of the specific polymer, but also the curability and physical properties of the cured film are impaired by mixing with the curable composition. And the curable composition can be colored.

(Pigment)
The pigment dispersion composition of the present invention contains a pigment. The pigment particles having a small particle diameter are uniformly and stably dispersed in the ink composition by the action of the specific polymer, whereby a sharp image with excellent color developability can be formed. There is no restriction | limiting in particular as a pigment which can be used by this invention, According to the objective, a well-known various pigment can be selected suitably and can be used. In addition, since a pigment is included as a colorant, an image obtained using a curable ink composition prepared using the pigment dispersion of the present invention is excellent in weather resistance.

As the pigment contained in the pigment dispersion composition of the present invention, all commercially available organic pigments and inorganic pigments, and those obtained by dyeing resin particles with a dye can be used. Furthermore, commercially available pigment dispersions and surface-treated pigments, for example, pigments dispersed in an insoluble resin or the like as a dispersion medium, or those obtained by grafting a resin on the pigment surface are also effective for the present invention. It can be used as long as it is not damaged.
Examples of these pigments include, for example, “Pigment Dictionary” (2000), edited by Seijiro Ito. Herbst, K.M. Hunger “Industrial Organic Pigments”, JP 2002-12607 A, JP 2002-188025 A, JP 2003-26978 A, and JP 2003-342503 A3.

  Examples of organic pigments and inorganic pigments contained in the pigment dispersion composition of the present invention include C.I. I. Pigment Yellow 1 (Fast Yellow G etc.), C.I. I. A monoazo pigment such as C.I. Pigment Yellow 74; I. Pigment Yellow 12 (disaji yellow, etc.), C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 3, C.I. I. Pigment yellow 16, C.I. I. Pigment yellow 83, C.I. I. Pigment yellow 155, C.I. I. Disazo pigments such as C.I. Pigment Yellow 219; I. Azo lake pigments such as C.I. Pigment Yellow 100 (eg Tartrazine Yellow Lake); I. Pigment yellow 95 (condensed azo yellow, etc.), C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 128, C.I. I. Condensed azo pigments such as C.I. Pigment Yellow 166; I. Acidic dye lake pigments such as C.I. Pigment Yellow 115 (such as quinoline yellow lake); I. Basic dye lake pigments such as CI Pigment Yellow 18 (Thioflavin Lake, etc.), anthraquinone pigments such as Flavantron Yellow (Y-24), isoindolinone pigments such as Isoindolinone Yellow 3RLT (Y-110), and quinophthalone yellow Quinophthalone pigments such as (Y-138), isoindoline pigments such as isoindoline yellow (Y-139), C.I. I. Nitroso pigments such as C.I. Pigment Yellow 153 (nickel nitroso yellow, etc.); I. Metal complex salt azomethine pigments such as C.I. Pigment Yellow 117 (copper azomethine yellow, etc.); I. Pigment yellow 120 (benzimidazolone yellow) C.I. I. Pigment yellow 151, C.I. I. Pigment yellow 175, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 181, C.I. I. And acetolone pigments such as CI Pigment Yellow 194.

  Examples of those exhibiting red or magenta color include C.I. I. Monoazo pigments such as CI Pigment Red 3 (Toluidine Red, etc.); I. Pigment red 1, C.I. I. Pigment red 4, C.I. I. B-naphthol pigments such as C.I. Pigment Red 6; I. Disazo pigments such as C.I. Pigment Red 38 (Pyrazolone Red B, etc.); I. Pigment Red 53: 1 (Lake Red C, etc.) and C.I. I. Pigment Red 57: 1 (Brilliant Carmine 6B etc.), C.I. I. Pigment red 52: 1, C.I. I. Azo lake pigments such as C.I. Pigment Red 48 (B-oxynaphthoic acid lake, etc.); I. Pigment red 144 (condensed azo red, etc.), C.I. I. Pigment red 166, C.I. I. Pigment red 220, C.I. I. Pigment red 214, C.I. I. Pigment red 221, C.I. I. Condensed azo pigments such as C.I. Pigment Red 242, C.I. I. Pigment Red 174 (Phloxine B lake, etc.), C.I. I. Acidic dye lake pigments such as C.I. Pigment Red 172 (Erythrosin Lake, etc.); I. Basic dye lake pigments such as C.I. Pigment Red 81 (Rhodamine 6G 'lake, etc.); I. Anthraquinone pigments such as C.I. Pigment Red 177 (eg, dianthraquinonyl red); I. Thioindigo pigments such as C.I. Pigment Red 88 (Thioindigo Bordeaux, etc.); I. Perinone pigments such as C.I. Pigment Red 194 (perinone red, etc.); I. Pigment red 149 (perylene scarlet, etc.), C.I. I. Pigment red 179, C.I. I. Pigment red 178, C.I. I. Pigment red 190, C.I. I. Pigment red 224, C.I. I. Pigment red 123, C.I. I. Perylene pigments such as C.I. Pigment Red 224; I. Pigment violet 19 (unsubstituted quinacridone), C.I. I. Pigment red 122 (quinacridone magenta, etc.), C.I. I. Pigment red 262, C.I. I. Pigment red 207, C.I. I. Quinacridone pigments such as C.I. Pigment Red 209; I. Isoindolinone pigments such as CI Pigment Red 180 (isoindolinone red 2BLT, etc.); I. Alizarin lake pigments such as C.I. Pigment Red 83 (Madalake, etc.); I. Pigment red 171, C.I. I. Pigment red 175, C.I. I. Pigment red 176, C.I. I. Pigment red 185, C.I. I. Naphtholone pigments such as C.I. Pigment Red 208; I. Naphthol AS lake pigments such as C.I. Pigment Red 247; I. Pigment red 2, C.I. I. Pigment red 5, C.I. I. Pigment red 21, C.I. I. Pigment red 170, C.I. I. Pigment red 187, C.I. I. Pigment red 256, C.I. I. Pigment red 268, C.I. I. Naphthol AS pigments such as C.I. Pigment Red 269; I. Pigment red 254, C.I. I. Pigment red 255, C.I. I. Pigment red 264, C.I. I. And diketopyrrolopyrrole pigments such as CI Pigment Red 27.

  Examples of pigments exhibiting blue or cyan colors include C.I. I. Disazo pigments such as C.I. Pigment Blue 25 (Dianisidine Blue, etc.); I. Pigment blue 15, C.I. I. Pigment blue 15: 1, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 15: 4, C.I. I. Pigment blue 15: 6, C.I. I. Phthalocyanine pigments such as C.I. Pigment Blue 16 (phthalocyanine blue, etc.); I. Acidic dye lake pigments such as C.I. Pigment Blue 24 (Peacock Blue Lake, etc.); I. Basic dye lake pigments such as C.I. Pigment Blue 1 (Viclotia Pure Blue BO Lake, etc.); I. Anthraquinone pigments such as C.I. Pigment Blue 60 (Indantron Blue, etc.); I. And alkali blue pigments such as CI Pigment Blue 18 (Alkali Blue V-5: 1).

Examples of the pigment exhibiting green include C.I. I. Pigment green 7 (phthalocyanine green), C.I. I. Phthalocyanine pigments such as C.I. Pigment Green 36 (phthalocyanine green); I. Pigment green 8 (nitroso green), C.I. I. And azo metal complex pigments such as CI Pigment Green 10.
Examples of orange pigments include C.I. I. An isoindoline pigment such as C.I. Pigment Orange 66 (isoindoline orange); I. Anthraquinone pigments such as C.I. Pigment Orange 51 (dichloropyrantron orange); I. Pigment orange 2, C.I. I. Pigment orange 3, C.I. I. Β-naphthol pigments such as C.I. Pigment Orange 5; I. Pigment orange 4, C.I. I. Pigment orange 22, C.I. I. Pigment orange 24, C.I. I. Pigment orange 38, C.I. I. Naphthol AS pigments such as CI Pigment Orange 74; I. Isoindolinone pigments such as CI Pigment Orange 61; I. Perinone pigments such as C.I. Pigment Orange 43; I. Pigment orange 15, C.I. I. Disazo pigments such as CI Pigment Orange 16; I. Pigment orange 48, C.I. I. Quinacridone pigments such as CI Pigment Orange 49; I. Pigment orange 36, C.I. I. Pigment orange 62, C.I. I. Pigment orange 60, C.I. I. Pigment orange 64, C.I. I. An acetolone pigment such as C.I. Pigment Orange 72; I. Pigment orange 13, C.I. I. And pyrazolone pigments such as CI Pigment Orange 34.
Examples of the pigment exhibiting brown include C.I. I. Pigment brown 25, C.I. I. And naphthron pigments such as CI Pigment Brown 32.

Examples of pigments exhibiting black color include carbon black, titanium black, C.I. I. Indazine pigments such as CI Pigment Black 1 (aniline black); I. Pigment black 31, C.I. I. And perylene pigments such as CI Pigment Black 32.
Examples of the white pigment include basic lead carbonate (2PbCO ₃ Pb (OH) ₂ , so-called silver white), zinc oxide (ZnO, so-called zinc white), titanium oxide (TiO ₂ , so-called titanium white), and titanium. Strontium acid (SrTiO ₃ , so-called titanium strontium white) can be used. The inorganic particles used for the white pigment may be a simple substance or, for example, oxides such as silicon, aluminum, zirconium and titanium, organometallic compounds, and composite particles with organic compounds.

  Here, titanium oxide has a smaller specific gravity than other white pigments, a large refractive index, and is chemically and physically stable, so that it has a large hiding power and coloring power as a pigment. Excellent durability against other environments. Therefore, it is preferable to use titanium oxide as the white pigment. Of course, other white pigments (may be other than the listed white pigments) may be used as necessary.

For dispersing the pigment, for example, a dispersing device such as a ball mill, a sand mill, an attritor, a roll mill, a jet mill, a homogenizer, a paint shaker, a kneader, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, or a wet jet mill is used. be able to.
When dispersing the pigment, the specific polymer of the present invention is added. Moreover, when adding a pigment, it is also possible to use a synergist according to various pigments as a dispersion aid if necessary. The dispersion aid is preferably added in an amount of 1 to 50 parts by mass with respect to 100 parts by mass of the pigment.

  As the dispersion medium for various components such as pigments in the pigment dispersion composition or the curable composition, it is preferable to use the polymerizable compound (d) as a dispersion medium from the viewpoint of not impairing the curability and the properties of the cured film. . Among these, it is preferable to select a polymerizable compound having a low viscosity from the viewpoints of dispersion suitability, ink composition handling properties, and inkjet discharge suitability. Thus, it is not necessary to volatilize the solvent, and it can be used as it is as the curable composition while maintaining the dispersed state.

  Here, the smaller the average particle diameter of the pigment used in the ink composition other than white, the better the color developability. Therefore, it is preferably about 0.01 to 0.4 μm, more preferably 0.02 to 0.3 μm. It is. The selection of pigment, dispersant, dispersion medium, dispersion conditions, and filtration conditions are set so that the maximum particle size is 3 μm or less, preferably 1 μm or less. The average particle diameter of the pigment used in the white ink composition is preferably about 0.05 to 1.0 μm, more preferably about 0.1 to 0.4 μm from the viewpoint of providing sufficient hiding properties. preferable. Similar to the ink compositions of other colors, the selection of the pigment, the dispersant and the dispersion medium, the dispersion conditions, and the filtration conditions are set so that the maximum particle diameter is 3 μm or less, preferably 1 μm or less.

By controlling the particle size, clogging of the head nozzle can be suppressed, and ink storage stability, ink transparency, and curing sensitivity can be maintained. In the present invention, since a specific polymer having excellent dispersibility and stability is used, a uniform and stable dispersion can be obtained even when a fine particle pigment is used.
The particle diameter of the pigment in the pigment dispersion composition or the curable composition can be measured by a known measurement method. Specifically, it can be measured by a centrifugal sedimentation light transmission method, an X-ray transmission method, a laser diffraction / scattering method, and a dynamic light scattering method.

The ratio of the pigment to the specific polymer in the pigment dispersion composition is preferably in the range of 5 to 100% in terms of solid content with respect to the mass of the pigment. More preferably, it is 5 to 80% of range, and the range of 5 to 60% is the most preferable. Within this range, the dispersibility of the pigment particles is good, and good coloration is exhibited when a curable composition is obtained.
When the pigment is an organic pigment, the pigment in the curable composition is preferably added in an amount of 1 to 20% by mass, more preferably 1.5 to 10% by mass in terms of solid content. Moreover, when the said pigment is an inorganic pigment, 1-30 mass% is preferable in conversion of solid content, and 2-25 mass% is more preferable.

<Curable composition>
When the specific polymer produced by the production method of the present invention is used, among the polymerizable compounds having a polymerizable functional group such as an ethylenic double bond or cyclic ether, the pigment can be finely and stably dispersed, and the pigment dispersion composition The product can be suitably used as a curable composition as it is. A curable composition is a composition which hardens | cures by providing energy, such as a heat | fever and light.
When the specific polymer produced by the production method of the present invention is used, the polymerizable compound serves as a solvent, so there is no need to use an organic solvent or the amount of the organic solvent used can be reduced. It is possible to reduce the organic solvent that causes the conversion without taking any special purification means. As a result, not only the curability can be improved, but also blocking can be suppressed.

In the curable composition and the curable ink composition of the present invention, the polymerizable compound (d) can be additionally used as necessary.
In the present invention, the curable ink composition refers to a curable composition limited to ink use.
When a polymerizable compound is additionally used in the curable composition and the curable ink composition, the total content of (d) the polymerizable compound in the curable composition and the curable ink composition is 50-95 mass% is suitable with respect to the total solid content, Preferably it is 60-92 mass%, More preferably, it is the range of 70-90 mass%. When used in less than this range, the curability tends to decrease.

  The curable composition preferably further contains a polymerization initiator, and when it contains a thermal polymerization initiator, it cures well by heating, and when it contains a photopolymerization initiator, it is irradiated by active energy rays. Harden. Here, the active energy ray is not particularly limited as long as it can impart energy capable of generating a starting species in the ink composition by the irradiation, and is broadly α-ray, γ-ray, X-ray, Including ultraviolet rays, visible rays, electron beams, etc. Among them, ultraviolet rays and electron beams are preferable, and ultraviolet rays are more preferable from the viewpoints of curing sensitivity and device availability. Therefore, the curable composition of the present invention is preferably one that can be cured by irradiating ultraviolet rays as radiation. As an ultraviolet light source, a mercury lamp, a metal halide lamp, a light emitting diode (LED), a semiconductor laser, a fluorescent lamp, or the like is used. In the present invention, it is preferable to use a mercury lamp, a metal halide lamp, or a light emitting diode as a light source, and it is more preferable to have an emission wavelength of 300 nm to 400 nm.

<Polymerization initiator>
The curable composition of the present invention preferably contains a polymerization initiator for radical polymerization or cationic polymerization, and more preferably contains a photopolymerization initiator.
The photopolymerization initiator in the present invention undergoes a chemical change through the action of light or the interaction with the electronically excited state of the sensitizing dye to generate at least one of radicals, acids and bases. A compound.
The photopolymerization initiator is an actinic ray to be irradiated, for example, an ultraviolet ray having a wavelength of 400 to 200 nm, a far ultraviolet ray, a g ray, an h ray, an i ray, a KrF excimer laser beam, an ArF excimer laser beam, an electron beam, an X ray, Those having sensitivity to a molecular beam or an ion beam can be appropriately selected and used.

  As the photopolymerization initiator, those known to those skilled in the art can be used without limitation. For example, Bruce M. et al. Monroe et al., Chemical Review, 93, 435 (1993). R. S. By Davidson, Journal of Photochemistry and biology A: Chemistry, 73.81 (1993); P. Faussier “Photoinitiated Polymerization—Theory and Applications”: Rapra Review vol. 9, Report, Rapra Technology (1998); Tsunooka et al. , Prog. Polym. Sci. , 21, 1 (1996). Also, chemical amplification type photoresists and compounds used for photocationic polymerization described in “Organic Materials for Imaging” edited by Organic Electronics Materials Study Group, Bunshin Publishing (1993), pages 187-192 are used. can do. Further, F.I. D. Saeva, Topics in Current Chemistry, 156, 59 (1990); G. Maslak, Topics in Current Chemistry, 168, 1 (1993); B. Shuster et al, JACS, 112, 6329 (1990); D. F. Also known is a group of compounds that cause oxidative or reductive bond cleavage through interaction with the electronically excited state of a sensitizing dye as described in Eaton et al, JACS, 102, 3298 (1980). It is done.

  Examples of the photopolymerization initiator include (i) aromatic ketones, (ii) aromatic onium salt compounds, (iii) organic peroxides, (iv) hexaarylbiimidazole compounds, (v) ketoxime ester compounds, Vi) a borate compound, (vii) an azinium compound, (viii) a metallocene compound, (ix) an active ester compound, (x) a compound having a carbon halogen bond, and the like are preferable.

  (I) Examples of aromatic ketones include “RADIATION CURING IN POLYMER SCIENCE AND TECHNOLOGY” P. FOUASSIER J.M. F. RABEK (1993), a compound having a benzophenone skeleton or a thioxanthone skeleton described in p77 to 117 is preferable, an α-thiobenzophenone compound described in Japanese Patent Publication No. 47-6416, a benzoin ether compound described in Japanese Patent Publication No. 47-3981, An α-substituted benzoin compound described in JP-B-47-22326, a benzoin derivative described in JP-B-47-23664, an aroylphosphonic acid ester described in JP-A-57-30704, and JP-B-60-26483 Dialkoxybenzophenones described in JP-B-60-26403, benzoin ethers described in JP-A-62-81345, JP-B-1-34242, US Pat. No. 4,318,791, European patent Description of specification No. 0284561A1 α-aminobenzophenones, p-di (dimethylaminobenzoyl) benzene described in JP-A-2-211452, thio-substituted aromatic ketone described in JP-A-61-194062, JP-A-58-15471 Acylphosphine oxides described in JP-B-2-9597, acylphosphine described in JP-B-2-9596, thioxanthones described in JP-B-63-61950, JP-B-59-42864 The coumarins described, monoacylphosphine oxides described in JP-B-60-8047, JP-B-63-40799, JP-A-3-101686, JP-A-5-345790, JP-A-6-298818 More preferred are bisacylphosphine oxides.

  (Ii) Aromatic onium salts include Group V, VI and VII elements of the Periodic Table, specifically N, P, As, Sb, Bi, O, S, Se, Te, or I fragrances Group onium salts are included. For example, iodonium salts described in European Patent No. 104143, US Pat. No. 4,837,124, Japanese Patent Laid-Open No. 2-150848, Japanese Patent Laid-Open No. 2-96514, European Patent Nos. 370693, 233567, and 297443 are disclosed. , 294442, 279210, and 422570, U.S. Pat. Nos. 3,902,144, 4,933,377, 4,760013, 4,734,444, and 2,833,827, sulfonium salts and diazonium salts (Such as benzenediazonium which may have a substituent), diazonium salt resins (formaldehyde resin of diazodiphenylamine, etc.), N-alkoxypyridinium salts, etc. (for example, US Pat. No. 4,743,528, JP 63-1383 No. 5, JP-A-63-142345, JP-A-63-142346, and JP-B-46-42363, specifically 1-methoxy-4-phenylpyridinium tetrafluoro And the compounds described in JP-B Nos. 52-147277, 52-14278, and 52-14279 are preferably used. Generates radicals and acids as active species.

  (Iii) The organic peroxide includes almost all organic compounds having one or more oxygen-oxygen bonds in the molecule. For example, 3,3′4,4′-tetra- (t-butylperoxide Oxycarbonyl) benzophenone, 3,3'4,4'-tetra- (t-amylperoxycarbonyl) benzophenone, 3,3'4,4'-tetra- (t-hexylperoxycarbonyl) benzophenone, 3,3 '4,4'-tetra- (t-octylperoxycarbonyl) benzophenone, 3,3'4,4'-tetra- (cumylperoxycarbonyl) benzophenone, 3,3'4,4'-tetra- (p Peroxyesters such as -isopropylcumylperoxycarbonyl) benzophenone and di-t-butyldiperoxyisophthalate are preferred.

  (Iv) Examples of hexaarylbiimidazoles include lophine dimers described in JP-B-45-37377 and JP-B-44-86516, such as 2,2'-bis (o-chlorophenyl) -4,4 '. , 5,5'-tetraphenylbiimidazole, 2,2'-bis (o-bromophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (o, p- Dichlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (o-chlorophenyl) -4,4', 5,5'-tetra (m-methoxyphenyl) biimidazole, 2,2'-bis (o, o'-dichlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (o-nitrophenyl) -4,4', 5 '-Tetraphenylbiimidazole, 2,2'-bis (o-methylphenyl) -4,4', 5,5'-tetraphenylbiimidazole, 2,2'-bis (o-trifluorophenyl) -4 4,4 ', 5,5'-tetraphenylbiimidazole and the like.

  (V) Examples of ketoxime esters include 3-benzoyloxyiminobutan-2-one, 3-acetoxyiminobutan-2-one, 3-propionyloxyiminobutan-2-one, 2-acetoxyiminopentane- 3-one, 2-acetoxyimino-1-phenylpropan-1-one, 2-benzoyloxyimino-1-phenylpropan-1-one, 3-p-toluenesulfonyloxyiminobutan-2-one, 2- And ethoxycarbonyloxyimino-1-phenylpropan-1-one.

  (Vi) Examples of the borate salt include compounds described in US Pat. Nos. 3,567,453, 4,343,891, European Patents 109,772, and 109,773. It is done.

  (Vii) Examples of the azinium salt compound include JP-A-63-138345, JP-A-63-142345, JP-A-63-142346, JP-A-63-143537, and JP-B-46. The compound group which has NO bond of -42363 gazette is mentioned.

(Viii) Examples of the metallocene compound include, for example, JP-A-59-152396, JP-A-61-151197, JP-A-63-41484, JP-A-2-249, and JP-A-2-4705. And the iron-arene complexes described in JP-A-1-304453 and JP-A-1-152109.
Examples of the titanocene compound include di-cyclopentadienyl-Ti-di-chloride, di-cyclopentadienyl-Ti-bis-phenyl, and di-cyclopentadienyl-Ti-bis-2,3,4. , 5,6-pentafluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2,3,5,6-tetrafluorophen-1-yl, di-cyclopentadienyl-Ti-bis -2,4,6-trifluorophen-1-yl, di-cyclopentadienyl-Ti-2,6-difluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2,4- Difluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis-2,3,4,5,6-pentafluorophen-1-yl, di-methylcyclopentadienyl-Ti- -2,3,5,6-tetrafluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis-2,4-difluorophen-1-yl, bis (cyclopentadienyl) -bis (2,6-difluoro-3- (pyridin-1-yl) phenyl) titanium, bis (cyclopentadienyl) bis [2,6-difluoro-3- (methylsulfonamido) phenyl] titanium, bis (cyclopenta And dienyl) bis [2,6-difluoro-3- (N-butylbialoyl-amino) phenyl] titanium.

  Examples of (ix) active ester compounds include, for example, European Patent Nos. 0290750, 046083, 156153, 271851, and 0388343, U.S. Pat. Nos. 3,901,710, and 4,181,531, Nitrobenzester compounds described in JP-A-60-198538 and JP-A-53-133022, European Patents 0199672, 84515, 199672, 0441115, and 0101122 No. 4,618,564, U.S. Pat. No. 4,371,605 and U.S. Pat. No. 4,431,774, and iminosulfonates described in JP-A Nos. 64-18143, 2-245756, and 4-36548. Compound, Shoko 62-6223 , JP-B-63-14340, and compounds described in each publication of JP-A No. 59-174831, and the like.

  (X) Examples of the compound having a carbon halogen bond include Wakabayashi et al., Bull. Chem. Soc. Examples include compounds described in Japan, 42, 2924 (1969), compounds described in British Patent 1388492, compounds described in JP-A-53-133428, compounds described in German Patent 3333724, and the like.

  Examples of the compound (x) having a carbon halogen bond include F.I. C. J. Schaefer et al. Org. Chem. 29, 1527 (1964), compounds described in JP-A-62-258241, compounds described in JP-A-5-281728, and the like. A compound as described in German Patent No. 2641100, a compound described in German Patent No. 3333450, a group of compounds described in German Patent No. 3021590, or German Patent No. 3021599 And the compound group described in the book.

  Preferable specific examples of the compounds represented by the above (i) to (x) include those shown below.

The photoinitiator as a polymerization initiator can be used individually by 1 type or in combination of 2 or more types.
The content of the photopolymerization initiator as a polymerization initiator in the curable composition is preferably 0.1 to 20% by mass, more preferably 0.5 to 15% by mass in terms of the total solid content of the curable composition. 1 to 10% by mass is preferable.

In the present invention, a sensitizing dye may be added for the purpose of improving the sensitivity of the photopolymerization initiator. As the sensitizing dye, those belonging to the following compounds and having an absorption wavelength in the range of 350 nm to 450 nm are preferable.
Examples of the sensitizing dye include polynuclear aromatics (eg, pyrene, perylene, triphenylene, anthracene), xanthenes (eg, fluorescein, eosin, erythrosin, rhodamine B, rose bengal), cyanines (eg, thiacarbox). Cyanine, oxacarbocyanine), merocyanines (eg, merocyanine, carbomerocyanine), thiazines (eg, thionine, methylene blue, toluidine blue), acridines (eg, acridine orange, chloroflavin, acriflavine), anthraquinones (eg, , Anthraquinone), squalium (eg, squalium), and coumarins (eg, 7-diethylamino-4-methylcoumarin).
Moreover, as a sensitizing dye, the compound represented by the following general formula (IX)-(XIII) is more preferable.

In formula (IX), A ¹ represents a sulfur atom or —NR ⁵⁰ —, R ⁵⁰ represents an alkyl group or an aryl group, and L ² represents a basic nucleus of the dye in combination with adjacent A ¹ and an adjacent carbon atom. R ⁵¹ and R ⁵² each independently represent a hydrogen atom or a monovalent nonmetallic atomic group, and R ⁵¹ and R ⁵² are bonded to each other to form an acidic nucleus of the dye. May be. W represents an oxygen atom or a sulfur atom.
In formula (X), Ar ¹ and Ar ² each independently represent an aryl group and are linked via a bond with —L ³ —. Here, L ³ represents —O— or —S—. W is synonymous with that shown in the general formula (IX).
In the formula (XI), A ² represents a sulfur atom or NR ⁵⁹ , L ⁴ represents a nonmetallic atomic group that forms a basic nucleus of the dye in combination with adjacent A ² and a carbon atom, R ⁵³ , R ⁵⁴ , R ⁵⁵ , R ⁵⁶ , R ⁵⁷ and R ⁵⁸ each independently represent a monovalent nonmetallic atomic group, and R ⁵⁹ represents an alkyl group or an aryl group.

In formula (XII), A ³ and A ⁴ each independently represent —S— or —NR ⁶² — or —NR ⁶³ —, and R ⁶² and R ⁶³ each independently represent a substituted or unsubstituted alkyl group, or Represents a substituted or unsubstituted aryl group, and L ⁵ and L ⁶ each independently represent a nonmetallic atomic group that forms a basic nucleus of a dye in cooperation with adjacent A ³ , A ⁴ and adjacent carbon atoms. , R ⁶⁰ and R ⁶¹ are each independently a hydrogen atom or a monovalent non-metallic atomic group, or may be bonded to each other to form an aliphatic or aromatic ring.
In formula (XIII), R ⁶⁶ represents an aromatic ring or a hetero ring which may have a substituent, and A ⁵ represents an oxygen atom, a sulfur atom or —NR ⁶⁷ —. R ⁶⁴ , R ⁶⁵ and R ⁶⁷ each independently represent a hydrogen atom or a monovalent non-metallic atomic group, and R ⁶⁷ and R ⁶⁴ and R ⁶⁵ and R ⁶⁷ are each aliphatic or aromatic. They can be joined to form a ring.

  Preferred specific examples of the compounds represented by the general formulas (IX) to (XIII) include the exemplified compounds (C-1) to (C-24) shown below.

(Co-sensitizer)
Furthermore, you may add the well-known compound which has an effect | action of further improving a sensitivity or suppressing the superposition | polymerization inhibition by oxygen as a co-sensitizer to the curable composition of this invention.
Such co-sensitizers include amines such as M.I. R. Sander et al., “Journal of Polymer Society”, Vol. 10, 3173 (1972), Japanese Patent Publication No. 44-20189, Japanese Patent Publication No. 51-82102, Japanese Patent Publication No. 52-134692, Japanese Patent Publication No. 59-138205. No. 60, 84305, JP 62-18537, JP 64-33104, Research Disclosure 33825, and the like. Examples include ethanolamine, p-dimethylaminobenzoic acid ethyl ester, p-formyldimethylaniline, p-methylthiodimethylaniline and the like.

Other co-sensitizers include thiols and sulfides, for example, thiol compounds described in JP-A-53-702, JP-B-55-500806, JP-A-5-142772, and JP-A-56- No. 75643, and more specifically, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, 2-mercaptobenzimidazole, 2-mercapto-4 (3H) -quinazoline, β-mercaptonaphthalene. Etc.
Other co-sensitizers include, for example, amino acid compounds (eg, N-phenylglycine), organometallic compounds described in Japanese Patent Publication No. 48-42965 (eg, tributyltin acetate), Japanese Patent Publication No. 55-34414. The hydrogen donor described in JP-A-6-308727, the sulfur compound described in JP-A-6-308727 (eg, trithiane, etc.), the phosphorus compound described in JP-A-6-250387 (diethylphosphite, etc.), Japanese Patent Application No. 6-191605 Si-H and Ge-H compounds described in the above No.

  The curable composition and curable ink composition of the present invention include an essential component of a pigment and a specific polymer, an additional polymerizable compound which is a preferable optional component, a sensitizing dye used together with the polymerization initiator, and a co-sensitization. In addition to the agent, various additives can be used in combination depending on the purpose. For example, an ultraviolet absorber can be used from the viewpoint of improving the weather resistance of the obtained image and preventing discoloration. In addition, an antioxidant can be added to improve the stability of the curable ink composition.

  The curable composition and curable ink composition of the present invention further include various organic and metal complex anti-fading agents, potassium thiocyanate, lithium nitrate, and thiocyanic acid for the purpose of controlling ejection properties. In order to improve the adhesiveness with conductive salts such as ammonium and dimethylamine hydrochloride and the recording medium, a trace amount of organic solvent can be added.

  In addition, various polymer compounds can be added to the curable composition and the curable ink composition of the present invention in order to adjust film properties. Examples of polymer compounds include acrylic polymers, polyvinyl butyral resins, polyurethane resins, polyamide resins, polyester resins, epoxy resins, phenol resins, polycarbonate resins, polyvinyl butyral resins, polyvinyl formal resins, shellacs, vinyl resins, acrylic resins. Rubber resins, waxes and other natural resins can be used. Two or more of these may be used in combination.

In addition, nonionic surfactants, cationic surfactants, organic fluoro compounds, and the like can be added to the curable composition and the curable ink composition of the present invention in order to adjust liquid properties.
In addition to the above, the curable composition and curable ink composition of the present invention include, for example, leveling additives, matting agents, waxes for adjusting film physical properties, polyolefins and PET, as necessary. In order to improve the adhesion to the recording medium such as a tackifier, a tackifier that does not inhibit the polymerization can be contained.

  The curable ink composition of the present invention preferably has an ink viscosity at a temperature at the time of ejection of 5 mPa · s or more and 30 mPa · s or less, and 20 mPa · s or less in consideration of ejection properties. More preferably, the composition ratio is suitably adjusted and determined so as to be in the above range. The ink viscosity at 25 ° C. (room temperature) is 200 mPa · s or less, preferably 100 mPa · s or less, and more preferably 50 mPa · s or less. By setting the viscosity at room temperature high, even when a porous recording medium is used, ink penetration into the recording medium can be prevented, uncured monomer can be reduced, and odor can be reduced. Dot bleeding at the time of landing can be suppressed, and as a result, the image quality is improved. When the ink viscosity at 25 ° C. is larger than 200 mPa · s, a problem occurs in the delivery of the ink liquid.

  The surface tension of the curable ink composition of the present invention is preferably 20 to 40 mN / m, more preferably 23 to 35 mN / m. When recording on various recording media such as polyolefin, PET, coated paper, uncoated paper, 20 mN / m or more is preferable from the viewpoint of bleeding and penetration, and 35 mN / m or less is preferable from the viewpoint of wettability.

The curable ink composition of the present invention thus adjusted is suitably used as an ink for inkjet recording. The curable ink composition is printed on a recording medium by an ink jet printer, and then the printed ink composition is cured by irradiation with radiation to perform recording.
In the printed matter obtained with this curable ink composition, the image portion is cured by irradiation with radiation such as ultraviolet rays, and the strength of the image portion is excellent. It can be used for various purposes such as formation of a receiving layer (image portion).

  Next, the curable ink composition of the present invention can be suitably used for inkjet recording. The ink jet recording method that can be employed in this case will be described below.

  In the ink jet recording method, it is preferable that the curable ink composition is heated to 40 to 80 ° C. to lower the viscosity of the curable ink composition to 30 mPa · s or less, and then ejected, and this method is used. High injection stability can be realized. In general, radiation curable ink compositions generally have a higher viscosity than aqueous inks, so that the viscosity fluctuation range due to temperature fluctuations during printing is large. The viscosity variation of this curable ink composition directly affects the droplet size and the droplet ejection speed, thereby causing image quality deterioration. Therefore, the curable ink composition temperature during printing is kept as constant as possible. It is necessary. The control range of the temperature of the curable ink composition is preferably set temperature ± 5 ° C, more preferably set temperature ± 2 ° C, and particularly preferably set temperature ± 1 ° C.

  One characteristic of the ink jet recording apparatus is that it includes a means for stabilizing the temperature of the curable ink composition, and the portion to be kept at a constant temperature is from the ink tank (the intermediate tank if there is an intermediate tank) to the nozzle ejection surface. All piping systems and members are targeted.

  The temperature control method is not particularly limited, but for example, it is preferable to provide a plurality of temperature sensors in each piping portion and perform heating control according to the ink composition flow rate and the environmental temperature. Further, the head unit to be heated is preferably thermally shielded or insulated so that the apparatus main body is not affected by the temperature from the outside air. In order to shorten the printer start-up time required for heating or to reduce the loss of thermal energy, it is preferable to insulate from other parts and reduce the heat capacity of the entire heating unit.

By adding a photopolymerization initiator as the polymerization initiator to the curable ink composition of the present invention, an actinic radiation curable curable ink composition is obtained.
The irradiation conditions of actinic radiation in such a curable ink composition will be described. A basic irradiation method is disclosed in JP-A-60-132767. Specifically, a light source is provided on both sides of the head unit, and the head and the light source are scanned by a shuttle method. Irradiation is performed after a certain period of time after ink landing. Further, the curing is completed by another light source that is not driven. In WO99 / 54415, as an irradiation method, a method using an optical fiber or a method in which a collimated light source is applied to a mirror surface provided on the side surface of the head unit to irradiate the recording unit with UV light is disclosed. In the present invention, these irradiation methods can be used.

  In addition, when the curable ink composition of the present invention is used, it is desirable that the curable ink composition is heated to a certain temperature and the time from landing to irradiation is 0.01 to 0.5 seconds, The irradiation is preferably performed after 0.01 to 0.3 seconds, more preferably after 0.01 to 0.15 seconds. Thus, by controlling the time from landing to irradiation to an extremely short time, it is possible to prevent the landing ink from bleeding before being cured. In addition, since the curable ink composition can be exposed to a porous recording medium before it penetrates deeper than the light source reaches, unreacted monomer remains, and as a result, odor is reduced. can do. By using the inkjet recording method and the curable ink composition of the present invention in combination, a great synergistic effect is brought about. In particular, when a curable ink composition having an ink viscosity at 25 ° C. of 200 mPa · s or less is used, a great effect can be obtained. By adopting such an ink jet recording method, the dot diameter of the landed ink can be kept constant even on various recording media having different surface wettability, and the image quality is improved. In addition, in order to obtain a color image, it is preferable to superimpose in order from the color with the lowest brightness. When inks with low lightness are stacked, it is difficult for the irradiation rays to reach the lower ink, and inhibition of curing sensitivity, increase of residual monomers, generation of odor, and deterioration of adhesion tend to occur. Irradiation can be performed by injecting all the colors and exposing them together, but exposure for each color is preferable from the viewpoint of promoting curing.

There is no restriction | limiting in particular as an inkjet recording device used for this invention, A commercially available inkjet recording device can be used. That is, in the present invention, recording can be performed on a recording medium (printed material) using a commercially available inkjet recording apparatus.
According to the preferred ejection conditions, the ink composition of the present invention repeatedly heats and cools. However, due to the function of the pigment dispersant, the pigment dispersibility can be maintained even when stored under such temperature conditions. This is advantageous in that it is possible to suppress the deterioration of the color, to obtain excellent color developability over a long period of time, and to suppress the deterioration of the dischargeability due to the aggregation of the pigment.

  The recording medium to which the ink composition of the present invention can be applied is not particularly limited, and various non-absorbing resin materials used for ordinary non-coated paper, coated paper, and so on, so-called soft packaging, or the like. A resin film formed into a film shape can be used, and examples of various plastic films include PET film, OPS film, OPP film, ONy film, PVC film, PE film, and TAC film. In addition, examples of the plastic that can be used as a recording medium material include polycarbonate, acrylic resin, ABS, polyacetal, PVA, and rubbers. Metals and glasses can also be used as the recording medium.

  The printed matter of the present invention can be obtained by printing the curable ink composition of the present invention on a recording medium with an ink jet printer, and then preferably irradiating the printed ink composition with actinic radiation and curing. it can. The printed matter of the present invention has a high-quality image with excellent color developability and sharpness because the ink used for image formation contains fine pigment particles uniformly and stably dispersed, and the weather resistance of the image Therefore, it can be applied to a wide range of fields.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to the form in these Examples.

  In addition, the molecular weight of the polymer in the synthesis example shown below represents a weight average molecular weight, and was measured by GPC (Shimadzu Corporation HPLC LC-10AD). Further, this GPC measurement was performed using Shodex GPC-KF-804 manufactured by Showa Denko KK as a column, tetrahydrofuran (THF) as an eluent, and 40 ° C. and a flow rate of 0.8 mL / second. The molecular weight was calculated by comparison with standard polystyrene.

(Synthesis Example 1)
<Synthesis of A-1 of [Chemical Formula 1]>
DBE dibasic ester (CH ₃ O ₂ C (CH ₂ ) _n CO ₂ CH ₃ n = 2-4) (trade name: manufactured by Aldrich, hereinafter referred to as DBE) 15.0 g, 3-dimethylaminopropylacrylamide 15. 6 g (manufactured by Tokyo Chemical Industry Co., Ltd.) and 0.328 g of thioglycerol (manufactured by Aldrich) were introduced into a nitrogen-substituted three-necked flask and stirred with a stirrer (Shinto Kagaku Co., Ltd .: Three-One Motor). The mixture was heated to 105 ° C. while flowing nitrogen into the flask. After adding 0.0437 g of VA-086 (2,2′-azobis [2-methyl-N- (2-hydroxyethyl) -propionamide] (manufactured by Wako Pure Chemical Industries, Ltd.), the mixture was stirred for 2 hours. 0.0237 g of VA-086 was added and heated and stirred for 4 hours at 115 ° C. After the reaction solution was allowed to cool at room temperature, 20 g of DBE was added and poured into 500 g of n-hexane. The obtained polymer was dried under reduced pressure to obtain poly (3-dimethylaminopropylacrylamide) (corresponding to A-1) having a diol at the terminal (number average molecular weight 4,600).

(Synthesis Example 2)
<Synthesis of [Chemical Formula 1] A-3>
DBE 15.0 g, N, N-dimethylaminoethyl methacrylate 15.7 g (manufactured by Tokyo Chemical Industry Co., Ltd.), and thioglycerol 0.432 g (manufactured by Aldrich) were introduced into a nitrogen-substituted three-necked flask. The mixture was heated and heated to 105 ° C. while flowing nitrogen into the flask. VA-086 (2,2′-azobis [2-methyl-N- (2-hydroxyethyl) -propionamide] (manufactured by Wako Pure Chemical Industries, Ltd.)) 0.0577 g was added, followed by stirring for 2 hours. 0.0288 g of VA-086 was added, and the mixture was heated and stirred for 4 hours at 115 ° C. After allowing the reaction solution to cool at room temperature, 20 g of DBE was added and poured into 700 g of n-hexane. The obtained polymer was dried under reduced pressure to obtain poly (N-dimethylaminoethyl methacrylate) (corresponding to A-3) having a diol at the end (number average molecular weight 3,500).

(Synthesis Example 3)
<Synthesis of A-4 of [Chemical Formula 1]>
15.0 g of propylene glycol-1-monomethyl ether-2-acetate, 21.53 g of 2-[[(butylamino) carbonyl] oxy] ethyl acrylate (manufactured by Aldrich), 0.866 g of thioglycerol (manufactured by Aldrich), The mixture was introduced into a nitrogen-substituted three-necked flask, stirred with a stirrer (Shinto Kagaku Co., Ltd .: Three-One Motor), heated while flowing nitrogen into the flask, and heated to 105 ° C. 0.115 g of the same VA-086 (manufactured by Wako Pure Chemical Industries, Ltd.) as in Synthesis Example 1 was added, followed by stirring for 2 hours. Furthermore, 0.0558g of VA-086 was added, and it heated and stirred at 115 degreeC for 4 hours. The reaction solution was allowed to cool at room temperature, 20 g of DBE was added, and the mixture was poured into 700 g of n-hexane. The obtained polymer was filtered off and dried under reduced pressure to obtain poly [2-[[(butylamino) carbonyl] oxy] ethyl acrylate] (corresponding to A-4) having a diol at the terminal. (Number average molecular weight 2,800)

(Synthesis Example 4)
<Synthesis of B-1A>
Three-necked flask in which 120 g of propylene glycol-1-monomethyl ether-2-acetate (manufactured by Wako Pure Chemical Industries, Ltd.), 100 g of methyl methacrylate (manufactured by Wako Pure Chemical Industries, Ltd.) and 0.865 g of thioglycerol (manufactured by Aldrich) were substituted with nitrogen. The mixture is stirred with a stirrer (Shinto Kagaku Co., Ltd .: Three-One Motor), heated while flowing nitrogen into the flask, and heated to 105 ° C. After adding 0.115g of VA-086, it stirred for 2 hours. Furthermore, 0.056g of VA-086 was added, and it heated and stirred at 115 degreeC for 4 hours. The reaction solution was allowed to cool at room temperature, 100 g of DBE was added, and the mixture was poured into 6000 g of n-hexane. The precipitated solid was separated by filtration and dried under reduced pressure to obtain poly (methyl methacrylate) (B-1A) having a diol at the end. (The B-1 compound having a number average molecular weight of 12,000)

(Synthesis Example 5)
<Synthesis of B-1B>
Three-necked flask in which 120 g of propylene glycol-1-monomethyl ether-2-acetate (manufactured by Wako Pure Chemical Industries, Ltd.), 100 g of methyl methacrylate (manufactured by Wako Pure Chemical Industries, Ltd.) and 1.97 g of thioglycerol (manufactured by Aldrich) were replaced with nitrogen. Then, the mixture is stirred with a stirrer (Shinto Kagaku Co., Ltd .: Three-One Motor) and heated to 105 ° C. while flowing nitrogen into the flask. After adding 0.262 g of the same VA-086 as in Synthesis Example 1, the mixture was stirred for 2 hours. Further, 0.131 g of VA-086 was added, and the mixture was heated and stirred at 115 ° C. for 4 hours. The reaction solution was allowed to cool at room temperature, 100 g of DBE was added, and the mixture was poured into 6000 g of n-hexane. The precipitated solid was separated by filtration and dried under reduced pressure to obtain poly (methyl methacrylate) (B-1B) having a diol at the terminal. (B-1 compound having a number average molecular weight of 6,000)

(Synthesis Example 6)
<Synthesis of P-1 DEGDA solution>
Three mouthpieces of diethylene glycol diacrylate (DEGDA) 23.3 g (SR230, manufactured by Sartomer), A-1 0.86 g, B-1A 9.0 g, tolylene diisocyanate 0.14 g (TDI, manufactured by Tokyo Chemical Industry Co., Ltd.) It introduce | transduced into the flask and stirred with the stirrer (Shinto Scientific Co., Ltd .: Three-one motor), and it heated up to 60 degreeC. The mixture was stirred for 4 hours to obtain a pigment dispersant P-1 DEGDA solution. (Number average molecular weight 37,000)

(Synthesis Example 7)
<Synthesis of P-1 DVE-3 Solution>
DVE-3 23.3 g (triethylene glycol divinyl ether, manufactured by BASF), A-1 0.86 g, B-1A 9.0 g, tolylene diisocyanate 0.14 g (TDI, manufactured by Tokyo Chemical Industry Co., Ltd.) The mixture is introduced into a three-necked flask, stirred with a stirrer (Shinto Kagaku Co., Ltd .: Three-One Motor), and heated to 60 ° C. The pigment dispersant P-1DVE-3 solution was obtained by stirring for 4 hours. (Number average molecular weight 32,000)

(Synthesis Example 8)
<Synthesis of P-2 DVE-3 solution>
DVE-3 23.3 g (manufactured by Aldrich), A-1 0.64 g, B-1B 9.11 g, tolylene diisocyanate 0.25 g (TDI, manufactured by Tokyo Chemical Industry Co., Ltd.) were introduced into a three-necked flask, The mixture is stirred with a stirrer (Shinto Kagaku Co., Ltd .: Three-One Motor) and heated to 60 ° C. The pigment dispersant P-2DVE-3 solution was obtained by stirring for 4 hours. (Number average molecular weight 53,000)

(Synthesis Example 9)
<Synthesis of P-6 DVE-3 Solution>
DVE-3 23.3 g (manufactured by Aldrich), A-1 1.9 g, B-1B 74.5 g, tolylene diisocyanate 0.51 g (TDI, manufactured by Tokyo Chemical Industry Co., Ltd.), diethylene glycol 0.14 g (sum) The product is introduced into a three-necked flask, stirred with a stirrer (Shinto Kagaku Co., Ltd .: Three-One Motor), and heated to 60 ° C. The pigment dispersant P-6DVE-3 solution was obtained by stirring for 4 hours. (Number average molecular weight 45,000)

(Synthesis Example 10)
<Comparison dispersant P-7 DBE solution>
DBE 23.3 g (manufactured by Aldrich), A-1 0.86 g, B-1A 9.0 g, tolylene diisocyanate 0.14 g (TDI, manufactured by Tokyo Chemical Industry Co., Ltd.) were introduced into a three-necked flask, and a stirrer ( The mixture is stirred with Shinto Kagaku Co., Ltd. (Three-One Motor) and heated to 60 ° C. A comparative pigment dispersant P-7 DBE solution was obtained by stirring for 4 hours. (Number average molecular weight 33,000)

Example 1
To the specific polymer solution shown below, a pigment and three kinds of polymerizable compounds shown in the following composition are added, put into a motor mill M50 (manufactured by Eiger), and zirconia beads having a diameter of 0.65 mm are used. Dispersion was performed at 9 m / s for 6 hours to obtain an active energy ray-curable ink stock solution. Next, a polymerization initiator was added to the ink stock solution and mixed gently, and then pressure filtered with a membrane filter to obtain an ink jet ink of Example 1.
-Pigment (Organic pigment: Acetone-based pigment PY120) 3.0 parts by mass-Specific polymer solution (P-1 DEGDA solution) 3.0 parts by mass-Polymerizable compound (dicyclopentenyloxyethyl acrylate, FA-512A) 40.0 parts by mass / polymerizable compound (phenoxyethylene glycol acrylate, AMP-10G, manufactured by Shin-Nakamura Chemical Co., Ltd.) 25.4 parts by mass / polymerizable compound (hexaacrylate, DPCA-60: Nippon Kayaku Co., Ltd.)
5.0 parts by mass / polymerization initiator (acylphosphine oxide compound, Lucirin TPO-L: manufactured by BASF Japan Ltd.) 5.0 parts by mass

(Examples 2 to 4)
The same procedure as in Example 1 was conducted except that the P-1 DEGDA solution, which is the specific polymer used in Example 1, was changed to a P-1DVE-3 solution, a P-2DVE-3 solution, and a P-6DVE solution, respectively. Inkjet inks of Examples 2 to 4 were obtained.

(Comparative Example 1)
Example 1 except that “Disperbyk-168” (manufactured by Big Chemie Japan Co., Ltd.), which is a commercially available pigment dispersant having a base in the main chain, was used in place of the P-1 DEGDA solution used in Example 1. In the same manner as described above, an inkjet ink of Comparative Example 1 was obtained.

(Comparative Example 2)
A comparative example was carried out in the same manner as in Example 1 except that “SOLSPERSE 55000” (manufactured by Nippon Lubrizol Co., Ltd.), which is a commercially available polyurethane-based dispersant, was used instead of the P-1 DEGDA solution used in Example 1. No. 2 inkjet ink was obtained.

(Comparative Example 3)
An inkjet ink of Comparative Example 3 was obtained in the same manner as in Example 1 except that the comparative dispersant P-7DBE solution synthesized in Synthesis Example 10 was used instead of the P-1 DEGDA solution used in Example 1. It was.

<Evaluation of ink composition>
The obtained inkjet ink was evaluated according to the following method. The results are shown in Table 1.
-Viscosity-
The viscosity at 40 ° C. of each inkjet ink was measured using an E-type viscometer.
Evaluation criteria are as follows, A is good, then B. C is bad.
A: Less than 30 mP · s B: More than 30 mP · s, less than 100 mP · s C: More than 100 mP · s

-Stability-
The dispersion state after each ink-jet ink was stored at 60 ° C. for 48 hours was evaluated by visual observation and change in viscosity.
◎: Precipitation does not occur and viscosity does not increase ○: Precipitation does not occur and viscosity increases slightly, but there is no problem with ejection performance △: Precipitation does not occur, but ejection performance decreases due to increase in viscosity However, it is a practically problematic level ×: the occurrence of precipitates is observed

-Average particle size-
About each inkjet ink, the median diameter was measured and evaluated using the light-scattering diffraction type particle size distribution measuring apparatus (LB500, the Horiba, Ltd. make).
Evaluation criteria are as follows, A is good, then B. C is bad.
A: Median diameter is less than 100 nm B: Median diameter is 100 nm or more and less than 250 nm C: Median diameter is 250 nm or more

-Curability-
The obtained ink composition was printed on a vinyl chloride sheet with an inkjet printer (printing density 300 dpi, droplet ejection frequency 4 kHz, nozzle number 64), and then with a Deep UV lamp (USHIO, SP-7) at 800 mJ / exposure under conditions such that the energy of cm ^2, and obtain a printed sample.
The cured film was touched with a finger, and the presence or absence of “stickiness” was evaluated according to the following criteria.
A: No stickiness B: Slightly sticky C: Extremely sticky

-Blocking resistance-
The obtained ink composition was printed on a vinyl chloride sheet with an inkjet printer (printing density 300 dpi, droplet ejection frequency 4 kHz, nozzle number 64), and then with a Deep UV lamp (USHIO, SP-7) 1500 mJ / exposure under conditions such that the energy of cm ^2, and obtain a printed sample.
Three print samples were stacked, a weight was placed so as to be 1 (g / cm ³ ), and the degree of adhesion to the sheet on which the print surface overlapped after 6 hours was evaluated according to the following criteria.
A: Not adhered at all B: Slightly adhered, but no print surface peeling.
C: There is peeling of the printing surface.

From Table 2, the ink of the example using the specific polymer obtained by the production method of the present invention as a pigment dispersant is cured with high sensitivity by irradiation with radiation and forms a high-quality image without stickiness. Can do. The pigment dispersion had a low viscosity, and when the ink composition was stored for a long period of time, both the dispersibility and the dispersion stability of the pigment were good without increasing the viscosity. Further, it was found that a printed matter excellent in blocking resistance was obtained, and the ink jet recording method was free from nozzle clogging.
On the other hand, in the comparative example using a commercially available polymer dispersant, the initial pigment dispersibility is good, but in particular, the storage stability (stability (60 ° C.)) under high temperature conditions is inferior, which causes a practical problem. It was a level. Further, curability and blocking resistance were inferior to the inks of the examples. Moreover, when the pigment dispersant which did not use a polymeric compound at the time of manufacture was used, the sclerosis | hardenability fall was seen.

Claims (13)

A method for producing a pigment dispersant in which at least the following (a), (b), and (c) are reacted in a polymerizable compound (d).
(A) a compound having a hydroxyl group and a pigment-adsorptive partial structure;
(B) a polymer selected from aliphatic polyester, poly (meth) acrylate, and polyether, and having a hydroxyl group or a primary amino group;
(C) Bifunctional or higher isocyanate compounds.   The compound (a) having a hydroxyl group and a pigment-adsorptive partial structure is a polymer having a number average molecular weight in the range of 500 to 5,000, and (b) the aliphatic polyester, poly (meth) acrylate, and The number average molecular weight of the polymer selected from polyether and having a hydroxyl group or a primary amino group is in the range of 350 to 15000, and (c) an isocyanate group contained in one molecule of the bifunctional or higher functional isocyanate compound. The method for producing a pigment dispersant according to claim 1, wherein the number is 2 to 6.   The pigment adsorbing partial structure in the compound (a) having a hydroxyl group and a pigment adsorbing partial structure is a carboxyl group, carboxylate, secondary amino group, tertiary amino group, amide bond, urea bond, urethane. The method for producing a pigment dispersant according to claim 1 or 2, which is at least one selected from a bond, a carbonate bond, and an imide bond.   (A) a polymer having a hydroxyl group and a pigment-adsorptive partial structure selected from polyamide, polyurethane, polyurea, and poly (meth) acrylamides, and a polymer having a hydroxyl group at the terminal; nitrogen-containing (meth) The compound comprising any one of a vinyl polymer obtained by reacting an acrylate; and a vinyl polymer obtained by reacting a carboxylic acid-containing (meth) acrylate. The manufacturing method of the pigment dispersant of any one of Claims 1.   The hydroxyl group or primary amino group is selected from (a) a hydroxyl group contained in a compound having a hydroxyl group and a pigment-adsorptive partial structure, and (b) an aliphatic polyester, poly (meth) acrylate, and polyether. The production of a pigment dispersant according to any one of claims 1 to 4, wherein the number of hydroxyl groups or primary amino groups contained in the group-containing polymer is 1 to 2 per molecule, respectively. Method.   The method for producing a pigment dispersant according to any one of claims 1 to 5, wherein the polymerizable compound (d) is an isocyanate non-reactive (meth) acrylate or vinyl ether.   The method for producing a pigment dispersant according to any one of claims 1 to 5, wherein the polymerizable compound (d) is a compound having an isocyanate nonreactive oxetanyl group.   A pigment dispersion composition comprising a pigment dispersant produced by the production method according to any one of claims 1 to 7 and a pigment.   A curable composition containing the pigment dispersion composition according to claim 8.   Furthermore, the curable composition of Claim 9 containing a polymerization initiator.   A curable ink composition comprising the curable composition according to claim 9.   The curable ink composition according to claim 11, which is for inkjet recording.   An ink jet recording method using the curable ink composition according to claim 12.