JP2017110175A - Ink, recorded matter, ink container, recording device, and recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink excellent in storage stability and discharge stability.SOLUTION: An ink comprises a pigment, a quinacridone compound represented by the specified general formula (1), and a copolymer having a structural unit such as the specified general formula (2).SELECTED DRAWING: Figure 1

Description

  The present invention relates to ink, a recorded matter, an ink container, a recording apparatus, and a recording method.

  The inkjet recording method is popular because it has the advantage that the process is simple and full color can be easily achieved compared to other recording methods, and a high-resolution image can be obtained even with an apparatus with a simple configuration. It is expanding from personal to office use, commercial printing and industrial printing. In such an ink jet recording method, a water-based ink composition using a water-soluble dye as a coloring material is mainly used. However, since it has a disadvantage of being inferior in water resistance and light resistance, it is a water-insoluble alternative to a water-soluble dye. Development of pigment inks using these pigments is underway.

  In inkjet printing for office use, plain paper is mainly used as a recording medium, and high image density is required. In general, when pigment ink is printed on plain paper, the pigment penetrates into the paper without staying on the paper surface, so the pigment density on the paper surface is lowered and the image density is lowered. If the pigment concentration in the ink is increased, the image density is increased, but the viscosity of the ink is increased and the ejection stability is lowered.

  In order to increase the drying speed of the ink adhering to the recording medium as a measure for high-speed printing, means for increasing the drying speed by adding a penetrant such as a hydrophobic solvent to the ink and allowing water to permeate the recording medium is taken. Therefore, it is required to satisfy the dispersion stability in both the aqueous solvent pigment dispersion and the hydrophobic solvent ink.

In addition, the water-based pigment ink used in the above-described ink jet recording method and writing instrument is different from the water-based dye ink prepared by dissolving the dye in water, and it is necessary to stably disperse the pigment insoluble in water for a long period of time. Therefore, various pigment dispersants have been developed.
For example, Patent Document 1 proposes a graft polymer containing an aromatic ring in the side chain. By using this graft polymer as a pigment dispersant, ink storage stability at 70 ° C. for 3 days is ensured. However, when the graft polymer described in Patent Document 1 is used as a pigment dispersant, it is insufficient in terms of long-term storage stability, and the pigment dispersibility of an ink to which an organic solvent has been added is reduced. Storage stability cannot be ensured.

  Patent Documents 2 to 4 disclose aqueous pigment dispersions in which a pigment derivative substituted with a sulfonic acid group and a surfactant type pigment dispersant are used in combination. However, the preservability corresponding to the hydrophobization of the ink for countermeasures against high-speed printing of the ink for inkjet recording is still insufficient. Therefore, an ink having good storage stability and excellent ejection stability has been desired.

  Accordingly, the present invention has been made in view of the above-described state of the art, and an object thereof is to provide an ink having excellent storage stability and ejection stability.

  In order to solve the above problems, the ink of the present invention comprises a pigment, a quinacridone compound represented by the following general formula (1), and a structural unit represented by the following general formula (2) or the following general formula (3). And a copolymer having the following.

(Wherein R ¹ , R ² , R ³ and R ⁴ represent a hydrogen atom, a halogen atom or an alkyl group having 1 to 4 carbon atoms, and may be the same or different. R ⁵ , R ⁶ and R 4 ⁷ represents an alkyl group or alkylene group having 1 to 4 carbon atoms, which may be the same or different, and m is 1 or 2.)

(In the formula, R ⁸ represents a hydrogen atom or a methyl group, and L ₁ represents an alkylene group having 2 to 16 carbon atoms.)

(In the formula, R ⁹ represents a hydrogen atom or a methyl group, L ₂ is a single bond or — (CH ₂ ) _n —O— in which an oxygen atom is bonded to biphenyl, and n is an integer of 2 to 16). is there.)

  According to the present invention, an ink excellent in storage stability and ejection stability can be provided.

1 is a perspective view schematically showing an example of a recording apparatus according to the present invention. It is a perspective view which shows typically an example of the ink storage container which concerns on this invention. It is a figure which shows the measurement result of the mass spectrometry in an example of the ink which concerns on this invention.

  The ink, recorded matter, ink container, recording apparatus and recording method according to the present invention will be described below with reference to the drawings. The present invention is not limited to the embodiments described below, and other embodiments, additions, modifications, deletions, and the like can be changed within a range that can be conceived by those skilled in the art, and any aspect is possible. As long as the functions and effects of the present invention are exhibited, the scope of the present invention is included.

  The ink of the present invention comprises a pigment, a quinacridone compound represented by the following general formula (1), and a copolymer having a structural unit represented by the following general formula (2) or the following general formula (3). It is characterized by including.

(Wherein R ¹ , R ² , R ³ and R ⁴ represent a hydrogen atom, a halogen atom or an alkyl group having 1 to 4 carbon atoms, and may be the same or different. R ⁵ , R ⁶ and R 4 ⁷ represents an alkyl group or alkylene group having 1 to 4 carbon atoms, which may be the same or different, and m is 1 or 2.)

(In the formula, R ⁸ represents a hydrogen atom or a methyl group, and L ₁ represents an alkylene group having 2 to 16 carbon atoms.)

(In the formula, R ⁹ represents a hydrogen atom or a methyl group, L ₂ is a single bond or — (CH ₂ ) _n —O— in which an oxygen atom is bonded to biphenyl, and n is an integer of 2 to 16). is there.)

Details will be described below.
The content of the copolymer in the ink is not particularly limited when used as a pigment dispersant and can be appropriately selected according to the purpose, but is preferably 10 to 100 parts by mass with respect to 100 parts by mass of the pigment. . If the content is within this range, a high image density can be obtained. Moreover, you may use another dispersing agent together in the range which does not impair the effect as a dispersing agent of a copolymer.

  The quinacridone compound represented by the general formula (1) is easily adsorbed on the pigment surface by π-π stacking with a pigment which is a coloring material in the ink, and particularly for a quinacridone pigment, it is due to hydrogen bonding between molecules. Since the adsorptivity is imparted, it is possible to realize excellent adsorptivity and maintain good dispersibility. In addition, it prevents aggregation of pigments due to steric hindrance of substituents containing dialkylamino groups, and by combining with an anionic dispersant with higher affinity, the dispersant can be more strongly adsorbed on the pigment surface by acid-base interaction. A stable dispersion state can be maintained over a long period of time.

  The number of substituents containing a dialkylamino group contained in the quinacridone compound represented by the general formula (1) has a distribution depending on production conditions. The number of these substituents contained in the quinacridone compound is represented by an average value unless otherwise separated and purified. The average introduction number is preferably 0.5 to 3.0, more preferably 1.0 to 2.0. If the number of substituents is small, the modification effect of the target pigment surface tends to be thin. If there are many substituents, the effect is high, but the affinity with the medium becomes strong and causes bleeding. There is.

In the general formula (1), the alkyl groups of R ¹ , R ² , R ³ and R ⁴ , the alkyl groups of R ⁵ , R ⁶ and R ⁷ are a methyl group having 1 to 4 carbon atoms, an ethyl group, a propyl group, Represents a butyl group and may be the same or different.
In addition, although it is thought that the substituent containing a dialkylamino group is couple | bonded with the site | part of the aromatic ring of a quinacridone skeleton, what was couple | bonded with the site | part of NH is not excluded.

In the general formula (2) and the general formula (3), R ⁸ and R ⁹ are a hydrogen atom or a methyl group. L ₁ is an alkylene group having 2 to 16 carbon atoms, preferably an alkylene group having 2 to 16 carbon atoms, and more preferably an alkylene group having 2 to 12 carbon atoms. L ₂ is a single bond or — (CH ₂ ) _n —O— in which an oxygen atom is bonded to biphenyl, and n is an integer of 2 to 16.

One end is an open end (open end, in other words, pendant structure), and the naphthyl group and biphenyl group present at the end via L in the end are formed by π-π stacking with a pigment which is a coloring material in water-based ink. , Has excellent pigment adsorbing power.
As understood from the description of the naphthyl group and biphenyl group present at the terminal via L in the pendant, the structural unit represented by the general formula (2) or the general formula (3) is typically May be a main chain of a copolymer having a pendant group such as a terminal naphthyl group, a biphenyl group, or a side chain carboxyl group depending on L ₁ and L ₂ . However, as a matter of course, the case where a part is included in the side chain is not excluded. For example, it is a well-known fact that it is difficult to completely eliminate secondary radical polymerization reactions that produce branched structures.

  In addition, when preparing the pigment dispersion in which the pigment is dispersed in water, if the copolymer of the present invention is used, a naphthyl group and a biphenyl group are present at the end of the side chain of the copolymer, so that it is adsorbed on the pigment surface. Since it has a high adsorptive power with the pigment, a highly dispersible long-term stable dispersion can be obtained.

  Therefore, according to the present invention, a pigment, a quinacridone compound represented by the general formula (1), a copolymer having a structural unit represented by the general formula (2) or the general formula (3), The pigment dispersion containing, becomes a long-term dispersion with high dispersibility, and can provide good storage stability. Accordingly, even when ink is used, good storage stability and ejection stability (ejection stability) can be obtained at a higher level.

  The weight average molecular weight Mw of a copolymer becomes like this. Preferably it is the range of 4000-80000, More preferably, it is the range of 5000-60000, More preferably, it is the range of 7000-40000. When the molecular weight is 4000 or more, the dispersion stability is improved due to the steric hindrance of the copolymer. Moreover, when it is 80,000 or less, an increase in a viscosity can be suppressed by reducing the entanglement between the copolymers, and the discharge stability is improved.

  The weight average molecular weight of the copolymer can be controlled to some extent by the polymerization temperature, the polymerization initiator amount, and the monomer concentration during the reaction. With respect to the polymerization temperature, a low molecular weight copolymer tends to be obtained when polymerized at a high temperature for a short time, and a high molecular weight copolymer tends to be obtained when polymerized at a low temperature for a long time.

By using the quinacridone compound represented by the general formula (1) and a copolymer in combination, the pigment can be more stably dispersed in the ink solvent.
In addition, when the ink is dried and the solid content ratio in the ink is increased in the head nozzle portion or the like of the ink jet printer, the pigment particles are aggregated. At this time, the copolymer having the structural unit represented by the general formula (2) or the general formula (3) may cause cross-linking and aggregation, which may reduce the redispersibility of the pigment, but has steric hindrance. By using together the quinacridone compound represented by the general formula (1), it is possible to prevent crosslinking between the pigments by the copolymer. By improving the redispersibility of the pigment in this way, a stable pigment dispersion state can be quickly reproduced by performing head cleaning even after ink drying, and excellent ejection reliability can be realized.

The quinacridone compound represented by the general formula (1) is 484.6 ± 1, 512.6 ± 1, 553.5 ± 1, 655 in mass spectrometry by matrix-assisted laser desorption / ionization time-of-flight mass spectrometry. Positive ion molecular peaks of 48 ± 1, 683.9 ± 1, and 724.7 ± 1, and 482.6 ± 1, 510.6 ± 1, 551.5 ± 1, 653.8 ± 1, 681.9 ± It may have at least one peak selected from 1 and 722.7 ± 1 negative ion molecular peaks. When these peaks appear, R ¹ , R ² , R ³ and R ⁴ in the general formula (1) are any one of a hydrogen atom, a methyl group and a chloro group, and are represented by m = 1 or 2. It can be said that a quinacridone compound is contained. When a compound represented by m = 1 is included, a positive ion molecule peak of 484.6 ± 1 and / or a negative ion molecule peak of 482.6 ± 1 or a positive ion molecule of 512.6 ± 1 Peak and / or negative ion molecular peak of 510.6 ± 1 and positive ion molecular peak of 553.5 ± 1 and / or negative ion molecular peak of 551.5 ± 1 are observed, and m = 2 When the compound represented is included, 655.8 ± 1 positive ion molecular peak, and / or 653.8 ± 1 negative ion molecular peak, 683.9 ± 1 positive ion molecular peak, and / or Alternatively, a negative ion molecular peak of 681.9 ± 1, a positive ion molecular peak of 724.7 ± 1, and / or a negative ion molecular peak of 722.7 ± 1 is observed.

  Mass analysis by matrix-assisted laser desorption / ionization time-of-flight mass spectrometry is performed using, for example, MALDI-TOFMS (matrix-assisted laser desorption / ionization time-of-flight mass spectrometer) autoflex III manufactured by Bruker Daltonics.

It is preferable that the copolymer of this invention has a repeating unit which consists of another hydrophilic polymerizable monomer other than the structural unit represented by the said General formula (2) or the said General formula (3).
Examples of the hydrophilic polymerizable monomer include (meth) acrylic acid or a salt thereof, maleic acid or a salt thereof, monomethyl maleate, itaconic acid, monomethyl itaconic acid, fumaric acid, 4-styrenesulfonic acid, 2-acrylamide. Anionic unsaturated ethylene monomers such as 2-methylpropanesulfonic acid or unsaturated ethylene monomer containing phosphoric acid, phosphonic acid, alendronic acid or etidronic acid; (meth) acrylic acid-2-hydroxyethyl, diethylene glycol mono (Meth) acrylate, triethylene glycol mono (meth) acrylate, tetraethylene glycol mono (meth) acrylate, polyethylene glycol mono (meth) acrylate, (meth) acrylamide, N-methylol (meth) acrylamide, N-vinyl Nonionic unsaturated ethylene monomers such as formamide, N-vinylacetamide, N-vinylpyrrolidone, acrylamide, N, N-dimethylacrylamide, Nt-butylacrylamide, N-octylacrylamide, Nt-octylacrylamide; dimethyl And cationic unsaturated ethylene monomers such as aminoethyl (meth) acrylamide, dimethylaminopropyl (meth) acrylamide, and methacryloylcholine chloride.

  The copolymer in the present invention may further have a repeating unit composed of another polymerizable monomer. The copolymer may be a copolymer of the structural unit represented by the general formula (2) and the structural unit represented by the general formula (3). It may be a copolymer of the structural unit represented by the general formula (3) and a repeating unit composed of other hydrophilic polymerizable monomer or other polymerizable monomer.

  There is no restriction | limiting in particular as said other polymerizable monomer, According to the objective, it can select suitably, For example, a polymerizable hydrophobic monomer, polymerizable surfactant, etc. are mentioned.

  Examples of the polymerizable hydrophobic monomer include unsaturated ethylene monomers having an aromatic ring such as α-methylstyrene, 4-t-butylstyrene, 4-chloromethylstyrene; methyl (meth) acrylate, (meta ) Ethyl acrylate, (n-butyl) (meth) acrylate, dimethyl maleate, dimethyl itaconate, dimethyl fumarate, lauryl (meth) acrylate (C12), tridecyl (meth) acrylate (C13), (meth) Tetradecyl acrylate (C14), pentadecyl (meth) acrylate (C15), hexadecyl (meth) acrylate (C16), heptadecyl (meth) acrylate (C17), nonadecyl (meth) acrylate (C19), (meth) Eicosyl acrylate (C20), helicosyl (meth) acrylate (C21), Alkyl (meth) acrylates such as docosyl methacrylate (C22); 1-heptene, 3,3-dimethyl-1-pentene, 4,4-dimethyl-1-pentene, 3-methyl-1-hexene, 4 -Methyl-1-hexene, 5-methyl-1-hexene, 1-octene, 3,3-dimethyl-1-hexene, 3,4-dimethyl-1-hexene, 4,4-dimethyl-1-hexene, -Nonene, 3,5,5-trimethyl-1-hexene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene , Unsaturated ethylene monomers having an alkyl group such as 1-nonadecene, 1-eicosene and 1-docosene. These may be used individually by 1 type and may use 2 or more types together.

  Based on the above, it is preferable that the copolymer having the structural unit represented by the general formula (2) or the general formula (3) has an anionic group or a nonionic group.

  Examples of the polymerizable surfactant include an anionic or nonionic surfactant having at least one unsaturated double bond group capable of radical polymerization in the molecule.

Examples of the anionic surfactant, ammonium sulfate base ^_(-SO 3 - _NH ^{4 +)} hydrocarbon compound having a sulfate group and an allyl group _{(-CH 2} -CH = CH 2), such as, ammonium sulfate base (-SO ₃ ^- NH ₄ ⁺⁾ sulfate group and methacrylic group, such as _{[-CO-C (CH 3) =} CH 2 ] a hydrocarbon compound having, or ammonium sulfate base ^_(-SO 3 - _NH ^{4 +)} sulfate, such as base and 1 An aromatic hydrocarbon compound having a —propenyl group (—CH═CH ₂ CH ₃ ) is exemplified.

  Specific examples include Eleminol JS-20 and RS-300 manufactured by Sanyo Kasei Co., Ltd., Aqualon KH-10, Aqualon KH-1025, Aqualon KH-05, Aqualon HS-10, Aqualon HS, manufactured by Daiichi Kogyo Seiyaku Co., Ltd. -1025, Aqualon BC-0515, Aqualon BC-10, Aqualon BC-1025, Aqualon BC-20, and Aqualon BC-2020.

Examples of the nonionic surfactant include hydrocarbon compounds or aromatics having a 1-propenyl group (—CH═CH ₂ CH ₃ ) and a polyoxyethylene group [— (C ₂ H ₄ O) _n —H]. A hydrocarbon compound etc. are mentioned. Specific examples thereof include Aqualon RN-20, Aqualon RN-2025, Aqualon RN-30, and Aqualon RN-50 manufactured by Daiichi Kogyo Seiyaku Co., Ltd. Latemu PD-104, Latemu PD-420, Latemu PD manufactured by Kao Corporation -430, Latem PD-450, and the like.

  The polymerizable surfactant is a mixture of one or two or more types with respect to the total amount of monomers represented by the structural unit represented by the general formula (2) or the general formula (2). You may use 1-10 mass%.

  The structure of the copolymer can be analyzed by using a general analytical method such as NMR or IR. Moreover, the molar ratio of the structural unit which comprises a copolymer can be calculated | required by the molar ratio of the monomer used when synthesize | combining a copolymer. Moreover, it can obtain | require by NMR from a copolymer.

  The quinacridone compound represented by the general formula (1) can be obtained by the reactions shown in the following reaction formulas (1) to (2). First, as shown in the following reaction formula (1), the quinacridone compound (A-1) and 2-chloro-N- (hydroxymethyl) acetamide are reacted in sulfuric acid and washed with water to obtain chloroacetamidomethylated quinacridone. Next, as shown in the reaction formula (2), (A-2) and a diamine are reacted to obtain a quinacridone mixture (A-3) represented by the general formula (1).

The general formula (2) can be obtained, for example, by the reactions shown in the following reaction formulas (3) to (4). First, as shown in the following reaction formula (3), naphthalene carbonyl chloride (B-1) and an excess amount of a diol compound are subjected to a condensation reaction in the presence of an acid acceptor such as an amine or pyridine to produce hydroxy naphthalene carboxylate. An alkyl ester (B-2) is obtained. Next, as shown in the following reaction formula (4), 2-methacryloyloxyethyl isocyanate (B-3) and the above (B-2) are reacted to obtain a monomer (B-4).
Then, if a monomer (B-4) and a 1 or more types of monomer are copolymerized in presence of a radical polymerization initiator, the copolymer in this invention will be obtained. Here, the molecular weight of the monomer (B-4) is 357 to 596 because L ₁ is an alkylene group having 2 to 16 carbon atoms and R ⁸ is a hydrogen atom or a methyl group in the general formula (2). .

The general formula (3) can be obtained, for example, by the reactions shown in the following reaction formulas (5) to (6). In the general formula (3), when L ₂ is a single bond, the acryloyloxyethyl isocyanate compound (C-1) and the hydroxybiphenyl compound (C-2) are reacted as shown in the following reaction formula (5). To obtain the monomer (C-3). When L ₂ is — (CH ₂ ) _n —O— in which an oxygen atom is bonded to biphenyl, and n is an integer of 2 to 16, acryloyloxy is represented by the following reaction formula (6). The monomer (C-5) is obtained by reacting the ethyl isocyanate compound (C-1) with the hydroxybiphenyl compound (C-4).
Then, if the monomer (C-3) or (C-5) is copolymerized with at least one monomer in the presence of a radical polymerization initiator, the copolymer in the present invention is obtained.

There is no restriction | limiting in particular as said radical polymerization initiator, According to the objective, it can select suitably. Examples thereof include peroxyketals, hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxydicarbonates, peroxy esters, cyano azobisisobutyronitrile, azobis (2-methylbutyronitrile), Examples thereof include azobis (2,2′-isovaleronitrile), non-cyano dimethyl-2,2′-azobisisobutyrate, and the like. Among these, organic peroxides and azo compounds are preferable, and azo compounds are particularly preferable because the molecular weight is easily controlled and the decomposition temperature is low.
There is no restriction | limiting in particular in content of the said radical polymerization initiator, Although it can select suitably according to the objective, 1-10 mass% is preferable with respect to the total amount of a polymerizable monomer.

In order to adjust the molecular weight of the polymer, an appropriate amount of a chain transfer agent may be added.
Examples of the chain transfer agent include mercaptoacetic acid, mercaptopropionic acid, 2-propanethiol, 2-mercaptoethanol, thiophenol, dodecyl mercaptan, 1-dodecanethiol, thioglycerol, and the like.

  The polymerization temperature is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 50 ° C to 150 ° C, more preferably 60 ° C to 100 ° C. The polymerization time is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 3 to 48 hours.

  A pigment constituting the ink of the present invention, a quinacridone compound represented by the general formula (1), and a copolymer having a structural unit represented by the general formula (2) or the general formula (3) The mass ratio is preferably in the following range from the viewpoint of the ability of the quinacridone derivative mixture and the copolymer to adsorb to the pigment. That is, the mass ratio of pigment: quinacridone derivative mixture: copolymer is preferably 70 to 100 / 0.1 to 20/5 to 100, more preferably 75 to 95 / 0.5 to 15 / 7.5 to 75. More preferably, it is 80-90 / 1-10 / 10-50.

<Ink>
Hereinafter, the organic solvent, water, pigment, color material, resin, additive, and the like used for the ink will be described.

<Organic solvent>
The organic solvent used in the present invention is not particularly limited, and a water-soluble organic solvent can be used. Examples thereof include ethers such as polyhydric alcohols, polyhydric alcohol alkyl ethers and polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines and sulfur-containing compounds.
Specific examples of the water-soluble organic solvent include, for example, ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 1,4-butane. Diol, 2,3-butanediol, 3-methyl-1,3-butanediol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol 2,4-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1,3-hexanediol, 2,5-hexanediol, 1,5-hexanediol, Glycerin, 1,2,6-hexanetriol, 2-ethyl-1,3-he Polyhydric alcohols such as sundiol, ethyl-1,2,4-butanetriol, 1,2,3-butanetriol, 2,2,4-trimethyl-1,3-pentanediol, petriol, ethylene glycol mono Polyhydric alcohol alkyl ethers such as ethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monophenyl ether, ethylene glycol mono Polyhydric alcohol aryl ethers such as benzyl ether, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl- -N-containing heterocyclic compounds such as pyrrolidone, 1,3-dimethyl-2-imidazolidinone, ε-caprolactam, γ-butyrolactone, formamide, N-methylformamide, N, N-dimethylformamide, 3-methoxy-N, Amides such as N-dimethylpropionamide and 3-butoxy-N, N-dimethylpropionamide, amines such as monoethanolamine, diethanolamine and triethylamine, sulfur-containing compounds such as dimethylsulfoxide, sulfolane and thiodiethanol, propylene carbonate, Examples thereof include ethylene carbonate.
In addition to functioning as a wetting agent, it is preferable to use an organic solvent having a boiling point of 250 ° C. or lower because good drying properties can be obtained.

A polyol compound having 8 or more carbon atoms and a glycol ether compound are also preferably used. Specific examples of the polyol compound having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, and the like.
Specific examples of glycol ether compounds include polyhydric alcohol alkyls such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether. Examples of ethers include polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.

  A polyol compound having 8 or more carbon atoms and a glycol ether compound can improve ink permeability when paper is used as a recording medium.

  The content of the organic solvent in the ink is not particularly limited and can be appropriately selected according to the purpose, but is preferably 10% by mass or more and 60% by mass or less from the viewpoint of the drying property and ejection reliability of the ink, 20 mass% or more and 60 mass% or less are more preferable.

<Water>
The water content in the ink is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 10% by mass or more and 90% by mass or less, and 20% by mass from the viewpoint of ink drying property and ejection reliability. % To 60% by mass is more preferable.

<Pigment>
Examples of pigments that can maintain good dispersibility by combining with the quinacridone compound represented by the general formula (1) used in the present invention include Pigment Red 4, 5, 9, 23, 48, 49, 52, 53. 57, 97, 112, 122, 123, 144, 146, 147, 149, 150, 166, 168, 170, 177, 180, 184, 185, 192, 202, 207, 214, 215, 216, 217, 220 , 221, 223, 224, 226, 227, 228, 238, 240, 242, 254, 255, 264, 272, C.I. I. Pigment Violet 19, 23, 29, 30, 37, 40, 50, etc. These may be used alone or in combination of two or more. Among these, C.I. can be obtained at a relatively low cost and has a great color tone and a wide color reproduction range. I. Pigment red 122, C.I. I. Pigment red 202 and C.I. I. It is preferable to use Pigment Violet 19 or a mixed crystal thereof. The dispersion will be described later.

<Color material>
The color material that can be used in addition to the pigment is not particularly limited, and pigments and dyes can be used.
An inorganic pigment or an organic pigment can be used as the pigment. These may be used alone or in combination of two or more. A mixed crystal may be used.
As the pigment, for example, a black pigment, a yellow pigment, a magenta pigment, a cyan pigment, a white pigment, a green pigment, an orange pigment, a glossy pigment such as gold or silver, a metallic pigment, or the like can be used.
Carbon black produced by known methods such as contact method, furnace method, thermal method in addition to titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, chrome yellow as inorganic pigments Can be used.
Organic pigments include azo pigments, polycyclic pigments (eg, phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, and quinofullerone pigments). Dye chelates (for example, basic dye type chelates, acidic dye type chelates), nitro pigments, nitroso pigments, aniline black, and the like can be used. Of these pigments, those having good affinity with the solvent are preferably used. In addition, resin hollow particles and inorganic hollow particles can also be used.
Specific examples of pigments include black for carbon black (CI pigment black 7) such as furnace black, lamp black, acetylene black, channel black, or copper, iron (CI pigment black 11). And metal pigments such as titanium oxide, and organic pigments such as aniline black (CI Pigment Black 1).
Further, for color use, C.I. I. Pigment Yellow 1, 3, 12, 13, 14, 17, 24, 34, 35, 37, 42 (yellow iron oxide), 53, 55, 74, 81, 83, 95, 97, 98, 100, 101, 104 , 108, 109, 110, 117, 120, 138, 150, 153, 155, 180, 185, 213, C.I. I. Pigment orange 5, 13, 16, 17, 36, 43, 51, C.I. I. Pigment Red 1, 2, 3, 5, 17, 22, 23, 31, 38, 48: 2, 48: 2 (Permanent Red 2B (Ca)), 48: 3, 48: 4, 49: 1, 52: 2, 53: 1, 57: 1 (Brilliant Carmine 6B), 60: 1, 63: 1, 63: 2, 64: 1, 81, 83, 88, 101 (Bengara), 104, 105, 106, 108 ( Cadmium red), 112, 114, 122 (quinacridone magenta), 123, 146, 149, 166, 168, 170, 172, 177, 178, 179, 184, 185, 190, 193, 202, 207, 208, 209, 213, 219, 224, 254, 264, C.I. I. Pigment violet 1 (rhodamine lake), 3, 5: 1, 16, 19, 23, 38, C.I. I. Pigment Blue 1, 2, 15 (phthalocyanine blue), 15: 1, 15: 2, 15: 3, 15: 4 (phthalocyanine blue), 16, 17: 1, 56, 60, 63, C.I. I. Pigment Green 1, 4, 7, 8, 10, 17, 18, 36, etc.
The dye is not particularly limited, and an acid dye, a direct dye, a reactive dye, and a basic dye can be used. One kind may be used alone, or two or more kinds may be used in combination.
Examples of the dye include C.I. I. Acid Yellow 17, 23, 42, 44, 79, 142, C.I. I. Acid Red 52, 80, 82, 249, 254, 289, C.I. I. Acid Blue 9, 45, 249, C.I. I. Acid Black 1, 2, 24, 94, C.I. I. Food Black 1, 2, C.I. I. Direct Yellow 1,12,24,33,50,55,58,86,132,142,144,173, C.I. I. Direct Red 1,4,9,80,81,225,227, C.I. I. Direct Blue 1, 2, 15, 71, 86, 87, 98, 165, 199, 202, C.I. I. Directed Black 19, 38, 51, 71, 154, 168, 171, 195, C.I. I. Reactive Red 14, 32, 55, 79, 249, C.I. I. Reactive black 3, 4, and 35 are mentioned.

  The content of the color material in the ink is preferably 0.1% by mass or more and 15% by mass or less, more preferably 1% by mass or more and 10% by mass from the viewpoints of improvement in image density, good fixability and ejection stability. It is as follows.

In order to disperse the pigment in the ink, a method of introducing a hydrophilic functional group into the pigment to form a self-dispersing pigment, a method of dispersing the pigment surface by coating with a resin, a method of dispersing using a dispersant, Etc.
Examples of a method for introducing a hydrophilic functional group into a pigment to form a self-dispersing pigment include a self-dispersing pigment that can be dispersed in water by adding a functional group such as a sulfone group or a carboxyl group to the pigment (for example, carbon) Can be used.
As a method for coating the surface of the pigment with a resin and dispersing it, a method in which the pigment is included in microcapsules and can be dispersed in water can be used. This can be paraphrased as a resin-coated pigment. In this case, it is not necessary that all pigments blended in the ink are coated with a resin, and within a range where the effects of the present invention are not impaired, uncoated pigments and partially coated pigments are dispersed in the ink. It may be.
Examples of the method of dispersing using a dispersant include a method of dispersing using a known low-molecular type dispersant or high-molecular type dispersant represented by a surfactant.
As the dispersant, for example, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, or the like can be used depending on the pigment.
RT-100 (nonionic surfactant) manufactured by Takemoto Yushi Co., Ltd. and naphthalenesulfonic acid Na formalin condensate can also be suitably used as a dispersant.
A dispersing agent may be used individually by 1 type, or may use 2 or more types together.

<Pigment dispersion>
An ink can be obtained by mixing a material such as water or an organic solvent with a color material. Further, it is also possible to produce an ink by mixing a pigment, other water, a dispersant, and the like into a pigment dispersion and mixing a material such as water or an organic solvent.
The pigment dispersion is obtained by dispersing water, a pigment, a pigment dispersant, and other components as required, and adjusting the particle size. For dispersion, a disperser is preferably used.
The particle size of the pigment in the pigment dispersion is not particularly limited, but the maximum frequency is 20 nm or more in terms of maximum number because the pigment dispersion stability is good and the image quality such as ejection stability and image density is also high. 500 nm or less is preferable and 20 nm or more and 150 nm or less are more preferable. The particle size of the pigment can be measured using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrack Bell Co., Ltd.).
The content of the pigment in the pigment dispersion is not particularly limited and may be appropriately selected depending on the intended purpose. However, from the viewpoint of obtaining good ejection stability and increasing the image density, 0.1% by mass. % To 50% by mass is preferable, and 0.1% to 30% by mass is more preferable.
The pigment dispersion is preferably degassed by filtering coarse particles with a filter, a centrifugal separator or the like, if necessary.

<Resin>
The type of resin contained in the ink is not particularly limited and can be appropriately selected according to the purpose. For example, urethane resin, polyester resin, acrylic resin, vinyl acetate resin, styrene resin, butadiene type Examples thereof include resins, styrene-butadiene resins, vinyl chloride resins, acrylic styrene resins, and acrylic silicone resins.
Resin particles made of these resins may be used. An ink can be obtained by mixing resin particles with a material such as a colorant or an organic solvent in a resin emulsion state in which water is dispersed as a dispersion medium. As said resin particle, what was synthesize | combined suitably may be used and a commercial item may be used. Moreover, these may be used individually by 1 type, or may be used in combination of 2 or more types of resin particles.

The volume average particle diameter of the resin particles is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 10 nm or more and 1,000 nm or less from the viewpoint of obtaining good fixability and high image hardness. It is more preferably 200 nm or less and particularly preferably 10 nm or more and 100 nm or less.
The volume average particle diameter can be measured using, for example, a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrack Bell Co., Ltd.).

  The resin content is not particularly limited and may be appropriately selected according to the purpose. However, from the viewpoint of fixability and ink storage stability, the content of the resin is 1% by mass or more and 30% by mass or less. Is preferable, and 5 mass% or more and 20 mass% or less are more preferable.

  The particle size of the solid content in the ink is not particularly limited and can be appropriately selected according to the purpose. From the viewpoint of improving the image quality such as ejection stability and image density, the maximum frequency in terms of the maximum number is converted. Is preferably 20 nm to 1000 nm, and more preferably 20 nm to 150 nm. The solid content includes resin particles, pigment particles, and the like. The particle size can be measured using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrack Bell Co., Ltd.).

<Additives>
If necessary, a surfactant, an antifoaming agent, an antiseptic / antifungal agent, a rust inhibitor, a pH adjuster, and the like may be added to the ink.

<Surfactant>
As the surfactant, any of silicone surfactants, fluorine surfactants, amphoteric surfactants, nonionic surfactants and anionic surfactants can be used.
There is no restriction | limiting in particular in silicone type surfactant, According to the objective, it can select suitably. Among them, those that do not decompose even at high pH are preferable, and examples thereof include side chain modified polydimethylsiloxane, both terminal modified polydimethylsiloxane, one terminal modified polydimethylsiloxane, and side chain both terminal modified polydimethylsiloxane. Those having an oxyethylene group or a polyoxyethylene polyoxypropylene group are particularly preferred because they exhibit good properties as an aqueous surfactant. In addition, as the silicone surfactant, a polyether-modified silicone surfactant can be used, and examples thereof include a compound in which a polyalkylene oxide structure is introduced into the side chain of the Si portion of dimethylsiloxane.
Examples of the fluorosurfactant include a perfluoroalkyl sulfonic acid compound, a perfluoroalkyl carboxylic acid compound, a perfluoroalkyl phosphate compound, a perfluoroalkyl ethylene oxide adduct, and a perfluoroalkyl ether group in the side chain. Polyoxyalkylene ether polymer compounds are particularly preferred because of their low foaming properties. Examples of the perfluoroalkyl sulfonic acid compound include perfluoroalkyl sulfonic acid, perfluoroalkyl sulfonate, and the like. Examples of the perfluoroalkylcarboxylic acid compound include perfluoroalkylcarboxylic acid and perfluoroalkylcarboxylate. Examples of the polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain include a sulfate ester salt of a polyoxyalkylene ether polymer having a perfluoroalkyl ether group in the side chain and a perfluoroalkyl ether group in the side chain. Examples thereof include salts of polyoxyalkylene ether polymers. As counter ions of salts in these fluorosurfactants, Li, Na, K, NH ₄ , NH ₃ CH ₂ CH ₂ OH, NH ₂ (CH ₂ CH ₂ OH) ₂ , NH (CH ₂ CH ₂ OH) ₃ etc. are mentioned.
Examples of amphoteric surfactants include lauryl aminopropionate, lauryl dimethyl betaine, stearyl dimethyl betaine, and lauryl dihydroxyethyl betaine.
Nonionic surfactants include, for example, polyoxyethylene alkylphenyl ether, polyoxyethylene alkyl ester, polyoxyethylene alkylamine, polyoxyethylene alkylamide, polyoxyethylene propylene block polymer, sorbitan fatty acid ester, polyoxyethylene sorbitan Examples include fatty acid esters and ethylene oxide adducts of acetylene alcohol.
Examples of the anionic surfactant include polyoxyethylene alkyl ether acetate, dodecylbenzene sulfonate, laurate, polyoxyethylene alkyl ether sulfate salt, and the like.
These may be used alone or in combination of two or more.

The silicone surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, side chain modified polydimethylsiloxane, both terminal modified polydimethylsiloxane, one terminal modified polydimethylsiloxane, side Since both ends of the chain are modified with polydimethylsiloxane, a polyether-modified silicone surfactant having a polyoxyethylene group or a polyoxyethylene polyoxypropylene group as a modifying group exhibits good properties as an aqueous surfactant. preferable.
As such a surfactant, an appropriately synthesized product or a commercially available product may be used. Commercially available products can be obtained from, for example, Big Chemie Co., Ltd., Shin-Etsu Chemical Co., Ltd., Toray Dow Corning Silicone Co., Ltd., Nippon Emulsion Co., Ltd., and Kyoeisha Chemical Co., Ltd.
The polyether-modified silicone surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, a polyalkylene oxide structure represented by the general formula (S-1) is represented by dimethylpolysiloxane. Examples thereof include those introduced into the side chain of Si part of siloxane.

(In the general formula (S-1), m, n, a, and b represent integers. R and R ′ represent an alkyl group and an alkylene group.)
A commercial item can be used as said polyether modified silicone type surfactant, For example, KF-618, KF-642, KF-643 (Shin-Etsu Chemical Co., Ltd.), EMALEX-SS-5602, SS- 1906EX (Japan Emulsion Co., Ltd.), FZ-2105, FZ-2118, FZ-2154, FZ-2161, FZ-2162, FZ-2163, FZ-2164 (Toray Dow Corning Silicone Co., Ltd.), BYK-33, BYK-387 (Bic Chemie Co., Ltd.), TSF4440, TSF4452, TSF4453 (Toshiba Silicon Co., Ltd.), etc. are mentioned.

As the fluorine-based surfactant, a fluorine-substituted compound having 2 to 16 carbon atoms is preferable, and a fluorine-substituted compound having 4 to 16 carbon atoms is more preferable.
Examples of the fluorosurfactant include perfluoroalkyl phosphate compounds, perfluoroalkylethylene oxide adducts, and polyoxyalkylene ether polymer compounds having a perfluoroalkyl ether group in the side chain. Among these, polyoxyalkylene ether polymer compounds having a perfluoroalkyl ether group in the side chain are preferred because of their low foaming properties, and are particularly fluorine-based compounds represented by the general formulas (F-1) and (F-2). A surfactant is preferred.

In the compound represented by the general formula (F-1), m is preferably an integer of 0 to 10 and n is preferably an integer of 0 to 40 in order to impart water solubility.
_{C n F 2n + 1- CH 2} CH (OH) CH 2 -O- (CH 2 CH 2 O) a -Y ··· Formula (F-2)
In the compound represented by the general formula (F-2), Y is H, or _C n _{F 2n + 1,} n is an integer from 1 to 6, or n is _{CH 2 CH (OH) CH 2} -C n F 2n + 1 is An integer of 4 to 6, or CpH _{2p + 1} , p is an integer of 1 to 19. a is an integer of 4-14.
A commercial item may be used as said fluorosurfactant. As this commercial item, for example, Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, S-145 (all manufactured by Asahi Glass Co., Ltd.); Fullrad FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, FC-431 (all manufactured by Sumitomo 3M Limited); Megafac F-470, F -1405, F-474 (all manufactured by Dainippon Ink & Chemicals, Inc.); Zonyl TBS, FSP, FSA, FSN-100, FSN, FSO-100, FSO, FS-300, UR (all FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW (all are corporations) (Manufactured by Male), Polyfox PF-136A, PF-156A, PF-151N, PF-154, PF-159 (Omnova), Unidyne DSN-403N (produced by Daikin Industries, Ltd.), and the like. Among these, FS-300 manufactured by Du Pont, FT-110, FT-250 manufactured by Neos Co., Ltd., and the like, have excellent print quality, particularly color developability, paper permeability, wettability, and leveling. FT-251, FT-400S, FT-150, FT-400SW, Polyfox PF-151N manufactured by Omninova, and Unidyne DSN-403N manufactured by Daikin Industries, Ltd. are particularly preferable.

  There is no restriction | limiting in particular as content of surfactant in an ink, Although it can select suitably according to the objective, From the point which is excellent in wettability and discharge stability, and image quality improves, it is 0.001 mass. % To 5% by mass is preferable, and 0.05% to 5% by mass is more preferable.

<Antifoaming agent>
There is no restriction | limiting in particular as an antifoamer, For example, a silicone type antifoamer, a polyether type | system | group antifoamer, a fatty-acid ester type | system | group antifoamer etc. are mentioned. These may be used alone or in combination of two or more. Among these, a silicone type antifoaming agent is preferable from the viewpoint of excellent foam breaking effect.

<Antiseptic and fungicide>
The antiseptic / antifungal agent is not particularly limited, and examples thereof include 1,2-benzisothiazolin-3-one.

<Rust preventive>
There is no restriction | limiting in particular as a rust preventive agent, For example, acidic sulfite, sodium thiosulfate, etc. are mentioned.

<PH adjuster>
The pH adjuster is not particularly limited as long as the pH can be adjusted to 7 or more, and examples thereof include amines such as diethanolamine and triethanolamine.

There is no restriction | limiting in particular as a physical property of an ink, According to the objective, it can select suitably, For example, it is preferable that a viscosity, surface tension, pH, etc. are the following ranges.
The viscosity at 25 ° C. of the ink is preferably 5 mPa · s or more and 30 mPa · s or less, preferably 5 mPa · s or more and 25 mPa · s or less from the viewpoint of improving the printing density and character quality and obtaining good discharge properties. More preferred. Here, for the viscosity, for example, a rotary viscometer (RE-80L manufactured by Toki Sangyo Co., Ltd.) can be used. Measurement conditions are 25 ° C., standard cone rotor (1 ° 34 ′ × R24), sample liquid amount 1.2 mL, rotation speed 50 rpm, and measurement is possible for 3 minutes.
The surface tension of the ink is preferably 35 mN / m or less and more preferably 32 mN / m or less at 25 ° C. from the viewpoint that the ink is suitably leveled on the recording medium and the drying time of the ink is shortened.
The pH of the ink is preferably 7 to 12 and more preferably 8 to 11 from the viewpoint of preventing corrosion of the metal member in contact with the liquid.

<Recording medium>
The recording medium is not particularly limited, and plain paper, glossy paper, special paper, cloth, and the like can be used. Good image formation is possible even with a non-permeable substrate.
The non-permeable base material is a base material having a surface with low water permeability and absorbability, and includes materials that do not open to the outside even if there are many cavities inside, more quantitatively. In the Bristow method, it refers to a substrate having a water absorption of 10 mL / m 2 or less from the start of contact until 30 msec 1/2.
As said non-permeable base material, plastic films, such as a vinyl chloride resin film, a polyethylene terephthalate (PET) film, a polypropylene, polyethylene, a polycarbonate film, can be used conveniently, for example.

<Recorded material>
The ink recorded matter of the present invention has an image formed using the ink of the present invention on a recording medium.
Recording can be performed by recording with an inkjet recording apparatus and an inkjet recording method.

<Recording apparatus and recording method>
The recording apparatus of the present invention has ink flying means for recording information or an image on a recording medium by causing the ink of the present invention to fly (discharge) from a recording head. In addition, the recording method of the present invention includes an ink flying step of recording information or an image on a recording medium by applying a stimulus to the ink of the present invention via an ink flying unit and causing the ink to fly (discharge) from the recording head. Including.
The ink of the present invention can be suitably used for various recording apparatuses using an ink jet recording method, such as a printer, a facsimile apparatus, a copying apparatus, a printer / fax / copier complex machine, and a three-dimensional modeling apparatus.
In the present application, a recording apparatus and a recording method are an apparatus that can eject ink, various processing liquids, and the like to a recording medium, and a method that performs recording using the apparatus. The recording medium means a medium on which ink or various processing liquids can be temporarily attached.
The recording apparatus can include not only a head portion that ejects ink but also means for feeding, transporting, and discharging a recording medium, and other devices called pre-processing devices and post-processing devices. .
The recording apparatus and the recording method may include a heating unit used in the heating step and a drying unit used in the drying step. The heating means and the drying means include, for example, a means for heating and drying the printing surface and the back surface of the recording medium. Although it does not specifically limit as a heating means and a drying means, For example, a warm air heater and an infrared heater can be used. Heating and drying can be performed before printing, during printing, after printing, and the like.
Further, the recording apparatus and the recording method are not limited to those in which significant images such as characters and figures are visualized by ink. For example, what forms patterns, such as a geometric pattern, etc. includes what forms a three-dimensional image.
Further, the recording apparatus includes both a serial type apparatus that moves the ejection head and a line type apparatus that does not move the ejection head, unless otherwise specified.
Furthermore, this recording apparatus can use not only a desktop type but also a wide recording apparatus that can print on an A0 size recording medium, for example, a continuous paper wound up in a roll shape as a recording medium. Also included are continuous paper printers.
An example of the recording apparatus will be described with reference to FIGS. FIG. 1 is a perspective view of the apparatus. FIG. 2 is an explanatory perspective view of the main tank. An image forming apparatus 400 as an example of a recording apparatus is a serial type image forming apparatus. A mechanism unit 420 is provided in the exterior 401 of the image forming apparatus 400. Each ink storage portion 411 of the main tank 410 (410k, 410c, 410m, 410y) for each color of black (K), cyan (C), magenta (M), yellow (Y) is packaged, for example, an aluminum laminate film It is formed by a member. The ink storage unit 411 is stored in, for example, a plastic container case 414. As a result, the main tank 410 is used as an ink cartridge for each color.
On the other hand, a cartridge holder 404 is provided on the inner side of the opening when the cover 401c of the apparatus main body is opened. A main tank 410 is detachably attached to the cartridge holder 404. Thus, the ink discharge ports 413 of the main tank 410 and the discharge heads 434 for the respective colors communicate with each other via the supply tubes 436 for the respective colors, and ink can be discharged from the discharge heads 434 to the recording medium.

The recording apparatus can include not only a portion that ejects ink but also a device called a pre-processing device or a post-processing device.
As one mode of the pretreatment device and the posttreatment device, as in the case of inks such as black (K), cyan (C), magenta (M), and yellow (Y), a pretreatment liquid and a posttreatment liquid are included. There is a mode in which a liquid container and a liquid discharge head are added, and a pretreatment liquid and a posttreatment liquid are discharged by an ink jet recording method.
As another aspect of the pretreatment apparatus and the posttreatment apparatus, there is an aspect in which, for example, a pretreatment apparatus or a posttreatment apparatus other than the ink jet recording method is provided by a blade coating method, a roll coating method, or a spray coating method.

  The method of using the ink is not limited to the ink jet recording method, and can be widely used. Besides the ink jet recording method, for example, a blade coating method, a gravure coating method, a bar coating method, a roll coating method, a dip coating method, a curtain coating method, a slide coating method, a die coating method, a spray coating method and the like can be mentioned.

The use of the ink of the present invention is not particularly limited and can be appropriately selected depending on the purpose. Furthermore, it can be used not only to form two-dimensional characters and images using ink, but also as a three-dimensional modeling material for forming a three-dimensional three-dimensional image (three-dimensional modeled object).
A known three-dimensional modeling apparatus for modeling a three-dimensional model can be used, and is not particularly limited. For example, a three-dimensional modeling apparatus including an ink storage unit, a supply unit, a discharge unit, a drying unit, or the like is used. be able to. The three-dimensional structure includes a three-dimensional structure obtained by repeatedly applying ink. Further, a molded product obtained by processing a structure provided with ink on a substrate such as a recording medium is also included. The molded product is obtained by subjecting a recorded material or a structure formed in a sheet shape or a film shape to a molding process such as heat stretching or punching, for example, an automobile, an OA device, an electric -It is suitably used for applications in which surfaces are decorated after decorating, such as meters for electronic devices, cameras, etc., and panels for operation units.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to the following Example.

(Mass spectrometry)
As an apparatus, MALDI-TOFMS (matrix-assisted laser desorption / ionization time-of-flight mass spectrometer) Bruflex Daltonics autoflex III was used for analysis under the following measurement conditions.
・ Measurement conditions [When measuring positive ions]
Ion Source1: 19.00 kV
Ion Source2: 16.65 kV
Lens: 8.20 kV
Reflector1: 21.00 kV
Reflector2: 9.70 kV
Laser: Smart beam 2 (wavelength: 355 nm, 532 nm, 1064 nm, 808 ± 5 nm)
Matrix: None Detection mode: reflector
Detection ion: Positive
Calibration: CsI3
[When measuring negative ions]
Ion Source1: 19.00 kV
Ion Source2: 16.65 kV
Lens: 8.50 kV
Reflector1: 21.00 kV
Reflector2: 9.70 kV
Laser: Smart beam 2 (wavelength: 355 nm, 532 nm, 1064 nm, 808 ± 5 nm)
Matrix: None Detection mode: reflector
Detection ion: Negative
Calibration: CsI3

(Weight average molecular weight of copolymer)
Shimadzu CTO-20A for the column thermostat, Shimadzu RID-10A for the detector, Shimadzu LC-20AD for the eluent flow path pump, Shimadzu DGU-20A for the degasser, autosampler Was measured by GPC method using SIL-20A manufactured by Shimadzu Corporation. For the column, use is made of Tosoh Corporation's water-based SEC column TSKgelG3000PWXL (exclusion limit molecular weight 2 × 10 ⁵ ), TSKgelG5000PWXL (exclusion limit molecular weight 2.5 × 10 ⁶ ), and TSKgelG6000PWXL (exclusion limit molecular weight 5 × 10 ⁷ ). It was. The sample was prepared to a concentration of 2 g / 100 mL with an eluent and used for measurement. As an eluent, an aqueous solution in which acetic acid and sodium acetate were adjusted to 0.5 mol / liter each was used. The column temperature was 40 ° C. and the flow rate was 1.0 mL / min.
Calibration curves using 9 types of polyethylene glycols with molecular weights of 1,065, 5,050, 24,000, 50,000, 107,000, 140,000, 250,000, 540,000, 920,000 as standard samples And the weight average molecular weight of the copolymer was determined based on the calibration curve.

(Synthesis example 1 of quinacridone mixture)
A 100 mL four-necked flask was charged with 40 g of sulfuric acid and cooled in an ice-water bath. To this, 5 g of quinacridone (manufactured by Tokyo Chemical Industry Co., Ltd.) was added little by little over 30 minutes so that the temperature did not exceed 5 ° C. After the addition, the mixture was stirred for 30 minutes while cooling in an ice-water bath. Next, 4 g of 2-chloro-N- (hydroxymethyl) acetamide (manufactured by Sigma-Aldrich Japan) was added little by little over 30 minutes so that the temperature did not exceed 5 ° C. After the addition, the mixture was stirred for 60 minutes while cooling in an ice-water bath, and then returned to room temperature and stirred for 24 hours. After completion of the stirring, the reaction solution was added little by little while stirring 400 g of ice water to obtain a reddish purple precipitate. This was filtered off with a glass filter, washed with 200 g of ion-exchanged water three times, and then heated and dried at 60 ° C. under reduced pressure to obtain 6.7 g of chloroacetamidomethylated quinacridone.

  A 50 mL three-necked flask was charged with 10 g of 3- (dimethylamino) -1-propylamine and cooled in an ice-water bath. To this, 3.5 g of chloroacetamidomethylated quinacridone was added little by little over 30 minutes so that the temperature did not exceed 5 ° C. After the addition, the mixture was stirred for 60 minutes while cooling in an ice-water bath, and then returned to room temperature and stirred for 24 hours. After the stirring was completed, the reaction solution was added little by little while stirring 200 g of ice water to obtain a reddish purple precipitate. This was filtered off with a glass filter, washed with 100 g of ion-exchanged water three times, and then heated and dried at 60 ° C. under reduced pressure to obtain 3.2 g of a red-purple quinacridone mixture. The infrared absorption spectrum (KBr tablet method) for this is shown in FIG.

Further, when the obtained quinacridone mixture was subjected to mass spectrometry, molecular ion peaks of [M + H] ⁺ of 484.6 and 655.8 were observed during positive ion measurement, and [M−H] ⁻ was 482 during negative ion measurement. A molecular ion peak of .6 was observed. It was found that quinacridone compounds represented by the following structural formulas (1) and (2) were mixed.
In the quinacridone compound represented by the following structural formulas (1) and (2), R ^{1 to} R ⁴ in the general formula (1) are hydrogen, R ⁵ and R ⁶ are methyl groups, and R ⁷ is a propylene group. , M is a mixture of 1 and 2.

Example 1
<Synthesis of monomer>
62.0 g (525 mmol) of 1,6-hexanediol (manufactured by Tokyo Chemical Industry Co., Ltd.) was dissolved in 700 mL of methylene chloride, and 20.7 g (262 mmol) of pyridine was added.
To this solution, a solution prepared by dissolving 50.0 g (262 mmol) of 2-naphthalenecarbonyl chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) in 100 mL of methylene chloride was dropped with stirring over 2 hours, and then stirred at room temperature for 6 hours. . After the obtained reaction solution was washed with water, the organic phase was isolated and dried over magnesium sulfate, and the solvent was distilled off. The residue was purified by silica gel column chromatography using a mixed solvent of methylene chloride / methanol (volume ratio 98/2) as an eluent to obtain 52.5 g of 2-naphthoic acid-2-hydroxyhexyl ester.

  Next, 42.1 g (155 mmol) of 2-naphthoic acid-2-hydroxyhexyl ester was dissolved in 80 mL of dry methyl ethyl ketone and heated to 60 ° C. To this solution, a solution prepared by dissolving 24.0 g (155 mmol) of 2-methacryloyloxyethyl isocyanate (produced by Showa Denko KK, Karenz MOI) in 20 mL of dry methyl ethyl ketone was added dropwise over 1 hour with stirring, and then 70 ° C. For 12 hours. After cooling to room temperature, the solvent was distilled off. The residue was purified by silica gel column chromatography using a mixed solvent of methylene chloride / methanol (volume ratio 99/1) as an eluent to obtain 57.0 g of the following monomer M-1.

<Synthesis of copolymer>
11.37 g (40 mmol) of Bremer PE-200 (manufactured by NOF Corporation) and 25.65 g (60 mmol) of monomer M-1 were dissolved in 130 mL of dry methyl ethyl ketone to prepare a monomer solution. After heating 10% of the monomer solution to 75 ° C. under an argon stream, 0.82 g (5 mmol) of 2,2′-azoiso (butyronitrile) (manufactured by Tokyo Chemical Industry Co., Ltd.) was dissolved in the remaining monomer solution. The solution was added dropwise over 5 hours and stirred at 75 ° C. for 6 hours. After cooling to room temperature, the resulting reaction solution was dropped into hexane. The supernatant was discarded, and a precipitated copolymer was obtained. The obtained copolymer was dissolved in tetrahydrofuran, evaporated, and dried under reduced pressure to obtain 33.35 g of a copolymer (weight average molecular weight Mw: 15200, number average molecular weight Mn: 6100).

<Preparation of pigment dispersion>
An aqueous solution having a concentration of the above copolymer of 20% was prepared. 20.0 g of this copolymer aqueous solution, 0.5 g of the quinacridone compound prepared in the synthesis example, 9.5 g of magenta pigment (CI Pigment Red 122, Clariant Ink Jet Magenta E 02) and 29.0 g of ion-exchanged water And stirred for 12 hours. The obtained mixture was circulated and dispersed for 1 hour at a peripheral speed of 10 m / s using a disk-type bead mill (Shinmaru Enterprises Co., Ltd., KDL type, media: using zirconia balls with a diameter of 0.1 mm), and then the pore size was 1 The mixture was filtered through a 2 μm membrane filter, and an adjusted amount of ion-exchanged water was added to obtain a pigment dispersion (solid content concentration: 20% by mass).

<Preparation of ink>
30.0 g of the pigment dispersion, 10.0 g of 1,3-butanediol, 10.0 g of glycerol, 10.0 g of 3-methoxy-N, N-dimethylpropionamide, Zonyl FS-300 (manufactured by Dupont, fluorine-based Surfactant, solid content concentration 40% by mass) 1.0 g and ion-exchanged water 39.0 g were mixed and stirred for 1 hour, and then filtered through a membrane filter having a pore size of 1.2 μm to obtain the ink of this example. Obtained.

(Example 2)
The magenta pigment used in the preparation of the pigment dispersion of Example 1 was C.I. I. A pigment dispersion and an ink were prepared in the same manner as in Example 1 except that Pigment Violet 19 and Hosterperm Red E5B 02 manufactured by Clariant were used.

(Example 3)
A pigment dispersion and an ink were prepared in the same manner as in Example 1 except that the magenta pigment used in the preparation of the pigment dispersion of Example 1 was changed as follows.
C. I. Pigment Red 122, Clariant's Ink Jet Magenta E 02 ... 5g
C. I. PigmentViolet 19, Hostaperm Red E5B 02 ... 4.5g made by Clariant

Example 4
The magenta pigment used in the preparation of the pigment dispersion of Example 1 was C.I. I. Pigment Red 122 / C.I. I. Pigment Violet 19 mixed crystal, Ink Jet Magenta E7B VP 3958 manufactured by Clariant Co. was used, and a pigment dispersion and ink were prepared in the same manner as in Example 1.

(Example 5)
The magenta pigment used in the preparation of the pigment dispersion of Example 1 was C.I. I. Pigment Red 202 / C.I. I. A pigment dispersion and an ink were prepared in the same manner as in Example 1 except that PigmentViolet 19 mixed crystal and BASF Cinquasia Magenta D 4500 J were used.

(Example 6)
A pigment dispersion and an ink were produced in the same manner as in Example 1 except that the Bremer PE-200 used for production of the copolymer of Example 1 was changed as follows.
BLEMMER PE-350 (manufactured by NOF Corporation) ... 17.54 g (40 mmol)

(Example 7)
A pigment dispersion and an ink were produced in the same manner as in Example 1 except that the Bremer PE-200 used for production of the copolymer of Example 1 was changed as follows.
BLEMMER PME-1000 (manufactured by NOF Corporation) ... 44.53 g (40 mmol)

(Example 8)
A pigment dispersion and an ink were prepared in the same manner as in Example 1 except that the synthesis of the copolymer of Example 1 and the preparation of the pigment dispersion were changed as follows.

<Synthesis of copolymer>
38.97 g (35 mmol) of Blemmer PME-1000 (manufactured by NOF Corporation), 25.65 g (60 mmol) of monomer M-1 and 0.36 g (5 mmol) of acrylic acid (manufactured by Tokyo Kasei) were added to 130 mL of dry methyl ethyl ketone. A monomer solution was prepared by dissolution. After heating 10% of the monomer solution to 75 ° C. under an argon stream, 0.82 g (5 mmol) of 2,2′-azoiso (butyronitrile) (manufactured by Tokyo Chemical Industry Co., Ltd.) was dissolved in the remaining monomer solution. The solution was added dropwise over 5 hours and stirred at 75 ° C. for 6 hours. After cooling to room temperature, the resulting reaction solution was dropped into hexane. The supernatant was discarded, and a precipitated copolymer was obtained. The obtained copolymer was dissolved in tetrahydrofuran, evaporated, and dried under reduced pressure to obtain 59.64 g of a copolymer (weight average molecular weight Mw: 15300, number average molecular weight Mn: 6100).

<Preparation of pigment dispersion>
The above copolymer was dissolved in a tetraethylammonium hydroxide solution so that the concentration of the copolymer was 20% and the pH was 8.0 to prepare an aqueous solution of the copolymer. 20.0 g of this copolymer aqueous solution, 0.5 g of the quinacridone compound prepared in the synthesis example, 9.5 g of magenta pigment (CI Pigment Red 122, Clariant Ink Jet Magenta E 02) and 29.0 g of ion-exchanged water And stirred for 12 hours. The obtained mixture was circulated and dispersed for 1 hour at a peripheral speed of 10 m / s using a disk-type bead mill (Shinmaru Enterprises Co., Ltd., KDL type, media: using zirconia balls with a diameter of 0.1 mm), and then the pore size was 1 The mixture was filtered through a 2 μm membrane filter, and an adjusted amount of ion-exchanged water was added to obtain a pigment dispersion (solid content concentration: 20% by mass).

Example 9
A pigment dispersion and an ink were prepared in the same manner as in Example 8 except that the acrylic acid used in the synthesis of the copolymer of Example 8 was changed as follows. Weight average molecular weight Mw of the obtained copolymer: 14700, number average molecular weight Mn: 5900)
Methacrylic acid (manufactured by Tokyo Chemical Industry) ... 0.43 g (5 mmol)

(Example 10)
The following monomer M-2 was synthesized by changing 1,6-hexanediol used in the synthesis of the monomer of Example 1 to ethylene glycol (manufactured by Tokyo Chemical Industry Co., Ltd.), and monomer M-2 was replaced by 22 instead of monomer M-1. A pigment dispersion and an ink were prepared in the same manner as in Example 1 except that a copolymer (weight average molecular weight Mw: 15000, number average molecular weight Mn: 6000) was synthesized using .28 g (60 mmol).

(Example 11)
The 1,6-hexanediol used in the synthesis of the monomer of Example 1 was changed to 1,12-dodecanediol (manufactured by Tokyo Chemical Industry Co., Ltd.) to synthesize the following monomer M-3, and monomer M instead of monomer M-1 A pigment dispersion and an ink were prepared in the same manner as in Example 1 except that 30.70 g (60 mmol) of -3 was used to synthesize a copolymer (weight average molecular weight Mw: 14900, number average molecular weight Mn: 6000).

(Example 12)
The following monomer M-4 was synthesized by replacing 1,6-hexanediol used in the synthesis of the monomer of Example 1 with 1,16-hexadecanediol (manufactured by Tokyo Chemical Industry Co., Ltd.), and monomer M instead of monomer M-1 A pigment dispersion and an ink were prepared in the same manner as in Example 1 except that a copolymer (weight average molecular weight Mw: 15400, number average molecular weight Mn: 6200) was synthesized using 34.07 g (60 mmol) of -4.

(Example 13)
The same procedure as in Example 1 was conducted except that the copolymer (weight average molecular weight Mw: 5100, number average molecular weight Mn: 2000) was synthesized by changing the amount of dry methyl ethyl ketone used in the synthesis of the copolymer of Example 1 to 600 ml. A pigment dispersion and ink were prepared.

(Example 14)
The same procedure as in Example 1 was conducted except that the copolymer (weight average molecular weight Mw: 7600, number average molecular weight Mn: 3000) was synthesized by changing the amount of dry methyl ethyl ketone used in the synthesis of the copolymer of Example 1 to 500 ml. A pigment dispersion and ink were prepared.

(Example 15)
The same procedure as in Example 1 was conducted except that the copolymer (weight average molecular weight Mw: 25600, number average molecular weight Mn: 10200) was synthesized by changing the amount of dry methyl ethyl ketone used in the synthesis of the copolymer of Example 1 to 70 ml. A pigment dispersion and ink were prepared.

(Example 16)
Except that the amount of dry methyl ethyl ketone used in the synthesis of the copolymer of Example 1 was changed to 40 ml and a copolymer (weight average molecular weight Mw: 39200, number average molecular weight Mn: 15900) was synthesized, the same as in Example 1. A pigment dispersion and ink were prepared.

(Example 17)
The same procedure as in Example 1 was conducted except that the copolymer (weight average molecular weight Mw: 51800, number average molecular weight Mn: 20700) was synthesized by changing the amount of dry methyl ethyl ketone used in the synthesis of the copolymer of Example 1 to 30 ml. A pigment dispersion and ink were prepared.

(Example 18)
<Synthesis of monomer>
2-phenylphenol (manufactured by Tokyo Chemical Industry Co., Ltd.) 40.0 g (235 mmol) and 6-bromo-1-hexanol (manufactured by Tokyo Chemical Industry Co., Ltd.) 51.06 g (282 mmol) were dissolved in 600 mL of methyl ethyl ketone. To this solution, 97.4 g of calcium carbonate was added and heated to reflux for 8 hours. After cooling to room temperature, the mixture was filtered and the filtrate was concentrated under reduced pressure. The obtained light brown liquid was dissolved in methylene chloride, and the organic layer was washed with water in a separatory funnel and dried over magnesium sulfate, and then the solvent was distilled off. The obtained residue was purified by silica gel column chromatography using methylene chloride as an eluent to obtain 105.3 g of 6- (2-phenylphenoxy) hexane-1-ol.

  Next, 14.10 g (52 mmol) of 6- (2-phenylphenoxy) hexane-1-ol was dissolved in 50 mL of dry methyl ethyl ketone and heated to 40 ° C. with stirring. To this solution, 8.09 g (52 mmol) of 2-methacryloyloxyethyl isocyanate (manufactured by Showa Denko KK, Karenz MOI) was added dropwise over 30 minutes, and then stirred at 70 ° C. for 12 hours. The residue obtained by cooling to room temperature and distilling off the solvent was purified by silica gel column chromatography using a mixed solvent of methylene chloride / methanol (volume ratio 98/2) as an eluent, and 18.88 g of the following monomer M-11 Got.

<Synthesis of copolymer>
11.37 g (40 mmol) of Bremer PE-200 (manufactured by NOF Corporation) and 25.53 g (60 mmol) of monomer M-11 were dissolved in 130 mL of dry methyl ethyl ketone to prepare a monomer solution. After heating 10% of the monomer solution to 75 ° C. under an argon stream, 0.82 g (5 mmol) of 2,2′-azoiso (butyronitrile) (manufactured by Tokyo Chemical Industry Co., Ltd.) was dissolved in the remaining monomer solution. The solution was added dropwise over 5 hours and stirred at 75 ° C. for 6 hours. After cooling to room temperature, the resulting reaction solution was dropped into hexane. The supernatant was discarded, and a precipitated copolymer was obtained. The obtained copolymer was dissolved in tetrahydrofuran, evaporated, and dried under reduced pressure to obtain 36.65 g of a copolymer (weight average molecular weight Mw: 15000, number average molecular weight Mn: 6000).

<Preparation of pigment dispersion>
An aqueous solution having a concentration of the above copolymer of 20% was prepared. 20.0 g of this copolymer aqueous solution, 0.5 g of the quinacridone compound prepared in the synthesis example, 9.5 g of magenta pigment (CI Pigment Red 122, Clariant Ink Jet Magenta E 02) and 29.0 g of ion-exchanged water And stirred for 12 hours. The obtained mixture was circulated and dispersed for 1 hour at a peripheral speed of 10 m / s using a disk-type bead mill (Shinmaru Enterprises Co., Ltd., KDL type, media: using zirconia balls with a diameter of 0.1 mm), and then the pore size was 1 The mixture was filtered through a 2 μm membrane filter, and an adjusted amount of ion-exchanged water was added to obtain a pigment dispersion (solid content concentration: 20% by mass).

<Preparation of ink>
30.0 g of the pigment dispersion, 10.0 g of 1,3-butanediol, 10.0 g of glycerol, 10.0 g of 3-methoxy-N, N-dimethylpropionamide, Zonyl FS-300 (manufactured by Dupont, fluorine-based Surfactant, solid content concentration 40% by mass) 1.0 g and ion-exchanged water 39.0 g were mixed and stirred for 1 hour, and then filtered through a membrane filter having a pore size of 1.2 μm to obtain the ink of this example. Obtained.

(Example 19)
The magenta pigment used for preparing the pigment dispersion of Example 18 was C.I. I. A pigment dispersion and an ink were prepared in the same manner as in Example 18 except that Pigment Violet 19 and Hostperm Red E5B 02 manufactured by Clariant were used.

(Example 20)
A pigment dispersion and an ink were prepared in the same manner as in Example 18 except that the magenta pigment used for preparing the pigment dispersion of Example 18 was changed as follows.
C. I. Pigment Red 122, Clariant's Ink Jet Magenta E 02 ... 5g
C. I. PigmentViolet 19, Hostaperm Red E5B 02 ... 4.5g made by Clariant

(Example 21)
The magenta pigment used for preparing the pigment dispersion of Example 18 was C.I. I. Pigment Red 122 / C.I. I. Pigment Violet 19 mixed crystal, Ink Jet Magenta E7B VP 3958 manufactured by Clariant Co. was used, and a pigment dispersion and ink were prepared in the same manner as in Example 18.

(Example 22)
The magenta pigment used for preparing the pigment dispersion of Example 18 was C.I. I. Pigment Red 202 / C.I. I. A pigment dispersion and an ink were prepared in the same manner as in Example 18 except that Pigment Violet 19 mixed crystal and Cinquasia Magenta D 4500 J manufactured by BASF were used.

(Example 23)
A pigment dispersion and an ink were produced in the same manner as in Example 18 except that the Bremer PE-200 used for production of the copolymer of Example 18 was changed as follows.
BLEMMER PE-350 (manufactured by NOF Corporation) ... 17.54 g (40 mmol)

(Example 24)
A pigment dispersion and an ink were produced in the same manner as in Example 18 except that the Bremer PE-200 used for production of the copolymer of Example 18 was changed as follows.
BLEMMER PME-1000 (manufactured by NOF Corporation) ... 44.53 g (40 mmol)

(Example 25)
A pigment dispersion and an ink were prepared in the same manner as in Example 18 except that the synthesis of the copolymer of Example 18 and the preparation of the pigment dispersion were changed as follows.

<Synthesis of copolymer>
38.97 g (35 mmol) of Blemmer PME-1000 (manufactured by NOF Corporation), 25.53 g (60 mmol) of monomer M-11 and 0.36 g (5 mmol) of acrylic acid (manufactured by Tokyo Chemical Industry) into 130 mL of dry methyl ethyl ketone. A monomer solution was prepared by dissolution. After heating 10% of the monomer solution to 75 ° C. under an argon stream, 0.82 g (5 mmol) of 2,2′-azoiso (butyronitrile) (manufactured by Tokyo Chemical Industry Co., Ltd.) was dissolved in the remaining monomer solution. The solution was added dropwise over 5 hours and stirred at 75 ° C. for 6 hours. After cooling to room temperature, the resulting reaction solution was dropped into hexane. The supernatant was discarded, and a precipitated copolymer was obtained. The obtained copolymer was dissolved in tetrahydrofuran, evaporated, and dried under reduced pressure to obtain 61.55 g of a copolymer (weight average molecular weight Mw: 15100, number average molecular weight Mn: 6000).

<Preparation of pigment dispersion>
The above copolymer was dissolved in a tetraethylammonium hydroxide solution so that the concentration of the copolymer was 20% and the pH was 8.0 to prepare an aqueous solution of the copolymer. 20.0 g of this copolymer aqueous solution, 0.5 g of the quinacridone compound prepared in the synthesis example, 9.5 g of magenta pigment (CI Pigment Red 122, Clariant Ink Jet Magenta E 02) and 29.0 g of ion-exchanged water And stirred for 12 hours. The obtained mixture was circulated and dispersed for 1 hour at a peripheral speed of 10 m / s using a disk-type bead mill (Shinmaru Enterprises Co., Ltd., KDL type, media: using zirconia balls with a diameter of 0.1 mm), and then the pore size was 1 The mixture was filtered through a 2 μm membrane filter, and an adjusted amount of ion-exchanged water was added to obtain a pigment dispersion (solid content concentration: 20% by mass).

(Example 26)
A pigment dispersion and an ink were prepared in the same manner as in Example 25 except that the acrylic acid used in the synthesis of the copolymer of Example 25 was changed as follows. (Weight average molecular weight Mw: 14800, number average molecular weight Mn: 5900)
Methacrylic acid (manufactured by Tokyo Chemical Industry) ... 0.43 g (5 mmol)

(Example 27)
The synthesis of the monomer of Example 18 was changed as follows to synthesize the following monomer M-12, and using 19.52 g (60 mmol) of monomer M-12 instead of monomer M-11, a copolymer (weight) A pigment dispersion and an ink were prepared in the same manner as in Example 18 except that the average molecular weight Mw: 15000 and the number average molecular weight Mn: 6000) were synthesized.

<Synthesis of monomer>
4-phenylphenol 12.00g (86mmol) was melt | dissolved in dry methyl ethyl ketone 50mL, and it heated and stirred to 40 degreeC. To this stirring solution, 12.68 g (74 mmol) of 2-methacryloyloxyethyl isocyanate (manufactured by Showa Denko KK, Karenz MOI) was added dropwise over 30 minutes, and then stirred at 70 ° C. for 12 hours. Subsequently, after cooling to room temperature, the solvent was distilled off. The residue was purified by silica gel column chromatography using a mixed solvent of methylene chloride / methanol (volume ratio 98/2) as an eluent to obtain 20.6 g of the following monomer M-12.

(Example 28)
The following monomer M-13 was synthesized in place of 2-bromoethanol (manufactured by Tokyo Chemical Industry Co., Ltd.) instead of 6-bromo-1-hexanol used in the synthesis of the monomer of Example 18, and instead of monomer M-11 A pigment dispersion and ink were prepared in the same manner as in Example 18 except that a copolymer (weight average molecular weight Mw: 15000, number average molecular weight Mn: 6000) was synthesized using 22.16 g (60 mmol) of monomer M-13. did.

(Example 29)
The following monomer M-14 was synthesized using 2-bromoethanol (manufactured by Tokyo Chemical Industry Co., Ltd.) instead of 6-bromo-1-hexanol used in the synthesis of the monomer of Example 18, and the monomer was replaced with the monomer M-11. A pigment dispersion and an ink were prepared in the same manner as in Example 18 except that 33.95 g (60 mmol) of M-14 was used to synthesize a copolymer (weight average molecular weight Mw: 15300, number average molecular weight Mn: 6200). .

(Example 30)
The same procedure as in Example 18 was performed except that the copolymer (weight average molecular weight Mw: 5200, number average molecular weight Mn: 2100) was synthesized by changing the amount of dry methyl ethyl ketone used in the synthesis of the copolymer of Example 18 to 600 ml. A pigment dispersion and ink were prepared.

(Example 31)
The same procedure as in Example 18 was conducted except that the copolymer (weight average molecular weight Mw: 7700, number average molecular weight Mn: 3100) was synthesized by changing the amount of dry methyl ethyl ketone used in the synthesis of the copolymer of Example 18 to 500 ml. A pigment dispersion and ink were prepared.

(Example 32)
The same procedure as in Example 18 was performed except that the copolymer (weight average molecular weight Mw: 25000, number average molecular weight Mn: 10,000) was synthesized by changing the amount of dry methyl ethyl ketone used in the synthesis of the copolymer of Example 18 to 70 ml. A pigment dispersion and ink were prepared.

(Example 33)
The same procedure as in Example 18 was performed except that the copolymer (weight average molecular weight Mw: 39600, number average molecular weight Mn: 15800) was synthesized by changing the amount of dry methyl ethyl ketone used in the synthesis of the copolymer of Example 18 to 40 ml. A pigment dispersion and ink were prepared.

(Example 34)
The same procedure as in Example 18 was performed except that the copolymer (weight average molecular weight Mw: 50600, number average molecular weight Mn: 20200) was synthesized by changing the amount of dry methyl ethyl ketone used in the synthesis of the copolymer of Example 18 to 30 ml. A pigment dispersion and ink were prepared.

(Comparative Example 1)
<Synthesis of Comparative Example Quinacridone Compound>
According to the method of Synthesis Example 1 of JP-A-2007-63407, a quinacridone compound represented by the following structural formula (3) was synthesized, and this was changed to the quinacridone compound used in the preparation of the pigment dispersion of Example 1. Except for the above, a pigment dispersion and an ink were prepared in the same manner as in Example 1.

(Comparative Example 2)
A pigment dispersion and an ink were prepared in the same manner as in Example 1 except that the quinacridone compound used in the preparation of the pigment dispersion of Example 1 was not added.

(Comparative Example 3)
A pigment dispersion and an ink were prepared in the same manner as in Example 1 except that the aqueous copolymer solution in the preparation of the pigment dispersion of Example 1 was not added.

(Comparative Example 4)
Monomer M-1 in the synthesis of the copolymer of Example 1 was replaced with a monomer having a structure represented by the following structural formula (4) to synthesize a copolymer, and 6.36 g of copolymer (weight average molecular weight Mw) : 14900, number average molecular weight Mn: 6000) A pigment dispersion and an ink were prepared in the same manner as in Example 1.

(Comparative Example 5)
<Synthesis of Comparative Example Quinacridone Compound>
According to the method of Synthesis Example 1 of JP-A-2007-63407, a quinacridone compound represented by the structural formula (3) was synthesized, and this was changed to the quinacridone compound used for preparing the pigment dispersion of Example 18. Prepared a pigment dispersion and an ink in the same manner as in Example 18.

(Comparative Example 6)
A pigment dispersion and an ink were prepared in the same manner as in Example 18 except that the quinacridone compound used in the preparation of the pigment dispersion of Example 18 was not added.

(Example 35)
A pigment dispersion and an ink were prepared in the same manner as in Example 1 except that the quinacridone mixture used in Example 1 was changed as follows.

<Synthesis example 2 of quinacridone mixture>
A 100 mL four-necked flask was charged with 40 g of sulfuric acid and cooled in an ice-water bath. Here, 5 g of 2,9-dimethylquinacridone (manufactured by Tokyo Chemical Industry Co., Ltd.) was added little by little over 30 minutes so that the temperature did not exceed 5 ° C. After the addition, the mixture was stirred for 30 minutes while cooling in an ice-water bath. Next, 4 g of 2-chloro-N- (hydroxymethyl) acetamide (manufactured by Sigma-Aldrich Japan) was added little by little over 30 minutes so that the temperature did not exceed 5 ° C. After the addition, the mixture was stirred for 60 minutes while cooling in an ice-water bath, and then returned to room temperature and stirred for 24 hours. After completion of the stirring, the reaction solution was added little by little while stirring 400 g of ice water to obtain a reddish purple precipitate. This was filtered off with a glass filter, washed with 200 g of ion-exchanged water three times, and then dried under heat at 60 ° C. to obtain 6.6 g of chloroacetamidomethylated quinacridone.

  A 50 mL three-necked flask was charged with 10 g of 3- (dimethylamino) -1-propylamine and cooled in an ice-water bath. To this, 3.5 g of chloroacetamidomethylated quinacridone was added little by little over 30 minutes so that the temperature did not exceed 5 ° C. After the addition, the mixture was stirred for 60 minutes while cooling in an ice-water bath, and then returned to room temperature and stirred for 24 hours. After the stirring was completed, the reaction solution was added little by little while stirring 200 g of ice water to obtain a reddish purple precipitate. This was filtered off with a glass filter, washed with 100 g of ion-exchanged water three times, and then heated and dried at 60 ° C. under reduced pressure to obtain 3.2 g of a red-purple quinacridone mixture. In this regard, the same infrared absorption spectrum as that of the quinacridone mixture used in Example 1 was obtained.

Further, when the obtained quinacridone mixture was subjected to mass spectrometry, molecular ion peaks of [M + H] ⁺ of 512.6 and 683.9 were observed during positive ion measurement, and [M−H] ⁻ was 510 during negative ion measurement. A molecular ion peak of .6 was observed. Thereby, it turned out that the quinacridone compound represented by following Structural formula (5) and Structural formula (6) is mixed.
In the quinacridone compound represented by the following structural formulas (5) and (6), R ¹ and R ⁴ in the general formula (1) are methyl groups, R ² and R ³ are hydrogen, R ⁵ and R ^6. Is a methyl group, R ⁷ is a propylene group, and m is a mixture of 1 and 2.

(Example 36)
A pigment dispersion and an ink were prepared in the same manner as in Example 1 except that the quinacridone mixture used in Example 1 was changed as follows.

<Synthesis example 3 of quinacridone mixture>
A 100 mL four-necked flask was charged with 40 g of sulfuric acid and cooled in an ice-water bath. Here, 5 g of 2,9-dichloroquinacridone (manufactured by Tokyo Chemical Industry Co., Ltd.) was added little by little over 30 minutes so that the temperature did not exceed 5 ° C. After the addition, the mixture was stirred for 30 minutes while cooling in an ice-water bath. Next, 4 g of 2-chloro-N- (hydroxymethyl) acetamide (manufactured by Sigma-Aldrich Japan) was added little by little over 30 minutes so that the temperature did not exceed 5 ° C. After the addition, the mixture was stirred for 60 minutes while cooling in an ice-water bath, and then returned to room temperature and stirred for 24 hours. After completion of the stirring, the reaction solution was added little by little while stirring 400 g of ice water to obtain a reddish purple precipitate. This was filtered off with a glass filter, washed with 200 g of ion-exchanged water three times, and then heated and dried at 60 ° C. under reduced pressure to obtain 6.7 g of chloroacetamidomethylated quinacridone.

  A 50 mL three-necked flask was charged with 10 g of 3- (dimethylamino) -1-propylamine and cooled in an ice-water bath. To this, 3.5 g of chloroacetamidomethylated quinacridone was added little by little over 30 minutes so that the temperature did not exceed 5 ° C. After the addition, the mixture was stirred for 60 minutes while cooling in an ice-water bath, and then returned to room temperature and stirred for 24 hours. After the stirring was completed, the reaction solution was added little by little while stirring 200 g of ice water to obtain a reddish purple precipitate. This was filtered off with a glass filter, washed with 100 g of ion-exchanged water three times, and then heated and dried at 60 ° C. under reduced pressure to obtain 3.3 g of a red-purple quinacridone mixture. In this regard, the same infrared absorption spectrum as that of the quinacridone mixture used in Example 1 was obtained.

Further, when the obtained quinacridone mixture was subjected to mass spectrometry, molecular ion peaks with [M + H] ⁺ of 552.5 and 723.7 were observed during positive ion measurement, and [M−H] ⁻ was 551 during negative ion measurement. A molecular ion peak of .5 was observed. Thereby, it turned out that the quinacridone compound represented by following Structural formula (7) and Structural formula (8) is mixed.
In the quinacridone compound represented by the following structural formula (7) and structural formula (8), R ¹ and R ⁴ in the general formula (1) are chlorine, R ² and R ³ are hydrogen, R ⁵ and R ⁶ are A methyl group, R ⁷ is a propylene group, and m is a mixture of 1 and 2.

  The following tables summarize the quinacridone compounds and copolymers of Examples 1-36 and Comparative Examples 1-6.

  For the pigment dispersions and inks described in Examples 1 to 36 and Comparative Examples 1 to 6, the storage stability of the pigment dispersion, the storage stability of the ink, and the ejection stability were evaluated by the methods described below. . The evaluation method is shown below. Moreover, an evaluation result is shown to Tables 5-8.

(Evaluation)
<Storage stability of pigment dispersion>
Each pigment dispersion was filled in a glass container and stored at 70 ° C. for 2 weeks. The rate of change in viscosity after storage with respect to the viscosity before storage was determined from the following formula and evaluated according to the following criteria.

For measurement of the viscosity, a viscometer (RE80L, manufactured by Toki Sangyo Co., Ltd.) was used, and the viscosity at 25 ° C. was measured at 50 revolutions. Ranks A and B are allowable ranges.
〔Evaluation criteria〕
A: Change rate of viscosity is within ± 3% B: Change rate of viscosity exceeds ± 3% and within ± 5% C: Change rate of viscosity exceeds ± 5% and within ± 8% D: Change in viscosity The rate exceeds ± 8% and within ± 10% E: The rate of change in viscosity exceeds ± 10% and within ± 30% F: The rate of change in viscosity exceeds ± 30% (cannot be evaluated due to gelation)

<Ink storage stability>
Each ink was filled in an ink cartridge and stored at 70 ° C. for 1 week. The change rate of the viscosity after storage with respect to the viscosity before storage was obtained from the following formula and evaluated according to the following criteria. Ranks A and B are allowable ranges.

  For measurement of the viscosity, a viscometer (RE80L, manufactured by Toki Sangyo Co., Ltd.) was used, and the viscosity at 25 ° C. was measured at 50 revolutions.

<Discharge stability>
Fill each ink into an ink jet printer (IPSiO GX-e5500 (Ricoh)), set it for 10 minutes continuously, put the ink on the head surface and put the moisture cap on the printer at 60 ° C 60% After being left for 1 month in an RH environment, cleaning was performed to return to the same level as before. Thereafter, an intermittent printing test was performed under the following conditions to evaluate discharge stability.
That is, after printing the print pattern chart continuously for 20 sheets, it is put into a pause state in which printing is not performed for 20 minutes, this is repeated 50 times, and after a total of 1000 copies are printed, the same chart is printed again. The presence or absence of streaks, white spots and jet disturbance in the 5% chart solid portion was evaluated visually according to the following criteria. In addition, the printing pattern printed each ink with 100% duty in the chart where the printing area of each color is 5% in the total area of the paper surface. The printing conditions were a recording density of 600 × 300 dpi and one-pass printing. The evaluation criteria are shown below. Ranks A and B are allowable ranges.
[Evaluation criteria]
A: There are no streaks, white spots, and jet turbulence in the solid part. B: Some stripes, white spots, and jet turbulence are found in the solid part. C: Stripes, white spots, and jet turbulence are found in the solid part. D: The whole solid part. There are streaks, white spots, and jet turbulence.

  Prepared using the quinacridone compound represented by the general formula (1) of the present invention in Examples 1 to 36 and the copolymer having the structural unit represented by the general formula (2) or the general formula (3). It can be seen that the pigment dispersion and ink thus obtained are superior in pigment dispersion and ink storage stability and ink ejection stability as compared with Comparative Examples 1-6.

400 Image forming apparatus 401 Exterior of image forming apparatus 401c Cover of apparatus main body 404 Cartridge holder 410 Main tank 410k, 410c, 410m, 410y For each color of black (K), cyan (C), magenta (M), yellow (Y) Main tank 411 Ink storage section 413 Ink discharge port 414 Storage container case 420 Mechanism section 434 Discharge head 436 Supply tube

Japanese Patent No. 5512240 Japanese Patent No. 4320991 Japanese Patent No. 5666956 JP 2007-63407 A

Claims (10)

It includes a pigment, a quinacridone compound represented by the following general formula (1), and a copolymer having a structural unit represented by the following general formula (2) or the following general formula (3). ink.
(Wherein R ¹ , R ² , R ³ and R ⁴ represent a hydrogen atom, a halogen atom or an alkyl group having 1 to 4 carbon atoms, and may be the same or different. R ⁵ , R ⁶ and R 4 ⁷ represents an alkyl group or alkylene group having 1 to 4 carbon atoms, which may be the same or different, and m is 1 or 2.)
(In the formula, R ⁸ represents a hydrogen atom or a methyl group, and L ₁ represents an alkylene group having 2 to 16 carbon atoms.)
(In the formula, R ⁹ represents a hydrogen atom or a methyl group, L ₂ is a single bond or — (CH ₂ ) _n —O— in which an oxygen atom is bonded to biphenyl, and n is an integer of 2 to 16). is there.)   The quinacridone compound is 484.6 ± 1, 512.6 ± 1, 553.5 ± 1, 655.8 ± 1, 683.9 ± in mass spectrometry by matrix-assisted laser desorption / ionization time-of-flight mass spectrometry. Positive ion molecular peaks of 1 and 724.7 ± 1 and negative of 482.6 ± 1, 510.6 ± 1, 551.5 ± 1, 653.8 ± 1, 681.9 ± 1 and 722.7 ± 1 The ink according to claim 1, wherein the ink has at least one peak selected from ionic molecule peaks.   The ink according to claim 1, wherein the pigment is a quinacridone pigment.   The ink according to claim 1, wherein the copolymer has an anionic group or a nonionic group. The ink according to claim 1, wherein L ₁ in the general formula (2) is an alkylene group having 2 to 12 carbon atoms.   The ink according to any one of claims 1 to 5, wherein the copolymer has a molecular weight Mw of 7,000 to 40,000.   A recorded matter, wherein information or an image is recorded on a recording medium using the ink according to claim 1.   An ink storage container comprising an ink storage section for storing ink, wherein the ink stored in the ink storage section is the ink according to claim 1. .   7. A recording apparatus comprising ink flying means for flying the ink according to claim 1 from a recording head to record information or an image on a recording medium. An ink flying step of recording information or an image on a recording medium by applying a stimulus to the ink according to any one of claims 1 to 6 via an ink flying means and causing the ink to fly from the recording head. Recording method.