JP6821958B2 - Dispersion, ink, ink container, inkjet recording method, inkjet recording device, and recorded material - Google Patents

Description

The present invention, minute Chikarada, ink, ink containing vessel, an ink jet recording method, an ink jet recording apparatus, and a recorded matter.

In recent years, in the field of image recording including inkjet technology, pigment ink is often used in consideration of water resistance and light resistance. However, the printed matter printed with the pigment ink has a problem that the pigment ink adheres to the surface of the recording medium and is easily peeled off, resulting in poor scratch resistance. Further, even in a wide range of uses including printing on a coated recording medium (coated paper), formation of a high-quality printed image is required.

Therefore, it is known to add a dispersion containing a polyurethane resin to the ink as a binder in order to obtain an ink having excellent abrasion resistance and capable of forming a printed image with high color development (high image quality).

For example, Patent Document 1 includes a polyol containing an aromatic polyester polyol and a hydrophilic group-containing polyol, a polyurethane obtained by reacting a polyisocyanate, and an aqueous medium, and the aromatic polyester polyol is aromatic. A binder for an inkjet printing ink, which has a structure of 1000 mmol / kg to 5000 mmol / kg, is disclosed.

However, the ink described in Patent Document 1 may not have a sufficient level of abrasion resistance. Further, in particular, when a coating recording medium that does not easily absorb ink is used, there is a problem that a blocking phenomenon occurs in which the contact surfaces of the printed matter stick to each other when the printed matter is overlapped. In addition, the ink containing the binder of Patent Document 1 may not be sufficient in terms of ink storage stability and ejection stability in an inkjet recording device.

In view of the above points, one aspect of the present invention is an ink resin for obtaining an ink which is excellent in abrasion resistance and blocking resistance in addition to storage stability and ejection stability and can form a high-density image. The purpose is to provide.

In order to solve the above problems, one state like the present invention includes a structure derived from a polyester polyol, a polyurethane resin having a structure derived from a short chain polyol having a hydrophilic group, the polyester polyol is represented by the following general have a structure represented by the formula (1), the number of moles of short chain polyols having a hydrophilic group, the value of the ratio to the sum of the number of moles and short-chain polyol of the polyester polyol is 0.17 This is a dispersion used as a binder for inkjet ink, in which an ink resin having a thickness of 0.35 or less is dispersed in an aqueous medium .

（ただし、一般式（１）中のＲ₁及びＲ_２は、それぞれ独立して水素原子又はアルキル基を表す。）

(However, R ₁ and R ₂ in the general formula (1) independently represent a hydrogen atom or an alkyl group.)

According to one aspect of the present invention, it is possible to provide an ink resin for obtaining an ink which is excellent in abrasion resistance and blocking resistance in addition to storage stability and ejection stability and can form a high-density image. ..

It is a figure for demonstrating the recording apparatus by one aspect of this invention. It is a perspective explanatory view of the main tank in one aspect of this invention.

<Resin for ink>
The ink resin according to one aspect of the present invention contains a polyurethane resin obtained by reacting a polyisocyanate with a polyester polyol having a structure having a bisphenol skeleton.

Further, the above-mentioned polyurethane resin for ink contains a polymer polyol component (relatively high molecular weight polyol) (A), a short chain polyol component (B), a polyisocyanate component (C), and chain extension as required. It may be a polyurethane resin obtained by reacting with the agent (D).

The content of the resin is not particularly limited and may be appropriately selected depending on the intended purpose. However, from the viewpoint of fixability and storage stability of the ink, 1% by mass or more and 30% by mass or less with respect to the total amount of the ink. Is preferable, and more preferably 2% by mass or more and 20% by mass or less.

<Polyester polyol>
The polymer polyol component (A) can be a polyester polyol. As the polyester polyol, an aromatic polyester polyol having a structure having a bisphenol skeleton (bisphenol skeleton structure) can be used.

In general, it is considered that an image having excellent abrasion resistance and blocking resistance can be formed by introducing an aromatic structure into the part of the structure of the polyurethane resin derived from the polyol and giving the resin rigidity. Be done.

As the polyol having an aromatic structure, for example, an aromatic polyester polyol that can be easily produced by utilizing a conventionally known condensation reaction can be used.

Therefore, the present inventors have studied urethane resins using various aromatic polyester polyols.

As a result, by using a resin containing a urethane resin having a structure derived from a polyester polyol containing a bisphenol skeleton structure as well as simply having an aromatic structure, very excellent scratch resistance, blocking resistance, and high image quality are obtained. It has been found that an ink capable of forming an image having a density and having excellent storage stability and ejection stability can be obtained.

Generally, in a compound having an aromatic structure, an interaction acts between aromatic rings. Moreover, the degree of freedom in the structure around the aromatic ring is low. Therefore, when a polyester polyol having an aromatic structure introduced is used as the polyol component of the urethane resin, excessive interaction between aromatic rings may occur depending on the introduced aromatic structure, and the urethane resin may aggregate. is there. As a result, when such a polyurethane resin is added to the ink, storage stability and ejection stability may be deteriorated. For example, when a polyester polyol having a structure containing a naphthalene ring is used, it may not be possible to say that the storage stability and ejection stability in inkjet printing are sufficient. Further, in some cases, the pigment and the resin are not uniformly mixed in the ink, and a non-uniform resin film is formed when the pigment and the resin are fixed on the recording medium, which may reduce the abrasion resistance and the blocking resistance.

However, among the polyester polyols containing an aromatic structure, the polyester polyol containing a bisphenol skeleton structure is characterized by having a relatively high degree of structural freedom around the aromatic ring. Therefore, while having the rigidity of the urethane resin, excessive interaction between aromatic rings is suppressed. As a result, the urethane resin can be prevented from agglutinating, so that an ink having excellent storage stability and ejection stability can be obtained. Further, since the resin and the pigment are uniformly mixed in the ink, a uniform and rigid resin film is formed when the resin and the pigment are fixed on the recording medium, and an image having excellent abrasion resistance and blocking resistance can be formed. it can.

The blocking phenomenon is particularly likely to occur when a recording medium that does not easily absorb ink, for example, coated paper, is used as the recording medium, or when a continuous form that is wound on a roll again after printing is used.

However, by using a polyester polyol containing a bisphenol skeleton structure as the polymer polyol component of the polyurethane resin, it is possible to suppress or prevent the blocking phenomenon even when a recording medium or a medium such as a continuous form that does not easily absorb ink is used. it can. In the present specification, the medium that does not easily absorb ink means, for example, a medium in which the amount of transfer to a pure recording medium at a contact time of 100 ms measured by a dynamic scanning liquid absorber is 30 mL / m ² or less. ..

Further, in a high-speed printing system, transfer stains on a transfer roller or the like may occur, so that image quality tends to deteriorate. However, due to the structure in which the polyester polyol contains the above-mentioned bisphenol skeleton structure, sufficient image quality can be achieved even in a high-speed printing system. Then, it is possible to improve the ink characteristics regarding the scratch resistance, the blocking resistance and the image density without impairing the storage stability and the ejection stability of the ink.

In addition, in this specification, a polyester polyol is a polyol having a relatively large molecular weight mainly containing an ester, and is not limited as long as it contains an ester obtained by condensation of a polyol and a polycarboxylic acid. The polyester polyol according to one aspect of the present invention also includes, for example, a polyether ester polyol, a polycarbonate polyester polyol, and the like.

The polymer polyol component (A) can also be a combination of the polyester polyol containing the above-mentioned structure having a bisphenol skeleton and the polymer polyol not containing the structure having a bisphenol skeleton.

Examples of polymer polyols that do not contain a structure having a bisphenol skeleton include polyester polyols that do not contain a structure having a bisphenol skeleton, polycaprolactone polyols, polycarbonate polyols, polyether polyols, and polymers in which polystyrene or polyacrylic nitrile is dispersed in polyols. Examples include polyols.

The number average molecular weight of the polyester polyol containing a structure having a bisphenol skeleton is preferably 500 or more and 3000 or less, and more preferably 1000 or more and 2000 or less. Within the above range, it is possible to form an image having excellent abrasion resistance and solvent resistance, and a urethane resin having excellent water resistance can be obtained.

Further, the number average molecular weight of the mixture of the polyester polyol having a structure having a bisphenol skeleton and the relatively high molecular weight polyol having no other structure having a bisphenol skeleton is also 500 or more and 3000 or less, preferably 1000 or more and 2000. It can be as follows.

The above average molecular weight can be measured by gel permeation chromatography (hereinafter referred to as GPC) using tetrahydrofuran as a solvent and polystyrene as a standard.

The hydroxyl value of the polyester polyol containing a structure having a bisphenol skeleton is preferably 30 mgKOH / g or more and 250 mgKOH / g or less, and more preferably 50 mgKOH / g or more and 150 mgKOH / g or less.

The hydroxyl value can be obtained by titrating with 0.5 M potassium hydroxide using tetrahydrofuran as a solvent.

<Bisphenol skeleton structure>
A polyester polyol containing a structure having a bisphenol skeleton is obtained by subjecting a low molecular weight polyol (monomer) (a1) containing a bisphenol skeleton structure and a polycarboxylic acid (monomer) (a2) to a condensation reaction as previously known. Be done.

Here, the bisphenol skeleton structure is not particularly limited as long as it is an organic skeleton obtained by synthesizing from a bisphenol compound. For example, it may be an organic skeleton containing two phenolic groups bonded via a carbon atom or a sulfur atom.

Examples of the bisphenol compound used for forming a structure having a bisphenol skeleton include 4,4'-dihydroxydiphenylsulfone, 4,4'-(1,3-phenylenediisopropyridene) bisphenol, and 4,4'-. Biphenol, 3,3'-biphenol, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A), 1,1-bis (4-hydroxyphenyl) -1-phenylethane (bisphenol AP), 2,2 -Bis (4-hydroxyphenyl) hexafluoropropane (bisphenol AF), 2,2-bis (4-hydroxyphenyl) butane (bisphenol B), bis (4-hydroxyphenyl) diphenylmethane (bisphenol BP), 2,2- Bis (3-methyl-4-hydroxyphenyl) propane (bisphenol C), bis (4-hydroxyphenyl) -2,2-dichloroethylene (bisphenol C), 1,1-bis (4-hydroxyphenyl) ethane (bisphenol E) ), Bis (4-hydroxyphenyl) methane (bisphenol F), 2,2-bis (4-hydroxy-3-isopropylphenyl) propane (bisphenol G), 1,3-bis (2- (4-hydroxyphenyl)) -2-propyl) benzene (bisphenol M), bis (4-hydroxyphenyl) sulfone (bisphenol S), 1,4-bis (2- (4-hydroxyphenyl) -2-propyl) benzene (bisphenol P), 5 , 5'-(1-methylethylidene) -bis [1,1'-(bisphenyl) -2-ol] propane (bisphenol PH), 1,1-bis (4-hydroxyphenyl) -3,3,5 Included are -trimethylcyclohexane (bisphenol TMC), 1,1-bis (4-hydroxyphenyl) cyclohexane (bisphenol Z), and alkylene oxide adducts thereof.

The hydrogen atom of the phenyl group in the bisphenol compound may be substituted with an organic group having 1 to 12 carbon atoms. Further, the above-mentioned bisphenol compound can be used alone or in combination of two or more kinds of bisphenol compounds.

Among the above compounds, it is preferable to select the bisphenol compound so that the bisphenol skeleton structure in the polyurethane resin has the structure represented by the following general formula (1).

（ただし、一般式（１）中のＲ₁及びＲ_２は、それぞれ独立して水素原子又はアルキル基を表す。）
上記のＲ₁及びＲ_２のアルキル基は、それぞれ独立して、炭素数１〜２を有するものであってよい。また、上記一般式（１）中のフェニル基の水素原子は、炭素数１〜１２の有機基、例えば、炭素数１〜３のアルキル基で置換されていてもよい。

(However, R ₁ and R ₂ in the general formula (1) independently represent a hydrogen atom or an alkyl group.)
The alkyl groups of R ₁ and R ₂ described above may independently have 1 to 2 carbon atoms. Further, the hydrogen atom of the phenyl group in the general formula (1) may be substituted with an organic group having 1 to 12 carbon atoms, for example, an alkyl group having 1 to 3 carbon atoms.

As the bisphenol compound, it is particularly preferable to select bisphenol A, bisphenol B, bisphenol E, bisphenol F, or alkylene oxide adducts thereof.

When a polyester polyol containing the structure represented by the general formula (1) is used, the degree of freedom in the structure around the aromatic rings is particularly high, and an appropriate force acts between the aromatic rings. It is possible to suppress the aggregation of the polyurethane resin and the non-uniform mixing of the ink and the pigment. Further, as compared with the case where a polyurethane resin containing an aromatic structure such as a naphthalene ring is used, excellent abrasion resistance, blocking resistance, storage stability and discharge stability can be realized. Therefore, the above-mentioned polyurethane resin can be suitably used in the form of a resin emulsion in printing on a coating recording medium such as coated paper or a recording medium wound up after printing, particularly for an inkjet ink.

Examples of the alkylene oxide added to the bisphenol compound include ethylene oxide and propylene oxide.

<Polycarboxylic acid>
The polyester polyol having a bisphenol skeleton structure according to one aspect of the present invention includes a structure having a bisphenol skeleton and a structure derived from a polycarboxylic acid. Specifically, the polyester polyol having a bisphenol skeleton structure is obtained by subjecting a low molecular weight polyol (a1) having a bisphenol skeleton structure and a polycarboxylic acid (a2) to a condensation reaction as is generally used in the past. Obtained by.

The polycarboxylic acid (a2) can be an aliphatic polycarboxylic acid having 4 to 12 carbon atoms, an aromatic polycarboxylic acid, or an esterified product or an anhydride thereof. Further, the polycarboxylic acid (a2) may be a dicarboxylic acid or a trivalent or higher valent polycarboxylic acid.

Examples of the polycarboxylic acid (a2) include aliphatic polycarboxylic acids such as succinic acid, adipic acid, sebacic acid and dodecanedioic acid, aromatic polycarboxylic acids such as terephthalic acid, isophthalic acid and phthalic acid, and these. Examples thereof include esterified products and anhydrides. Above all, it is preferable to use an aromatic dicarboxylic acid because it can improve scratch resistance, blocking resistance, and image density.

The structure derived from the polycarboxylic acid (a2) preferably includes a structure represented by the general formula (2) or a structure represented by the general formula (3), and the structure is represented by the general formula (3). Is particularly preferable.

＜ポリエステルポリオール中のその他の成分＞

<Other components in polyester polyol>

In addition to the components of the polyol (a1) having a bisphenol skeleton structure and the components of the polycarboxylic acid (a2), the polyester polyol is a low molecular weight polyol (monomer) other than the polyol (a1) having a bisphenol skeleton structure, if necessary. ) Ingredients may be included. The low molecular weight polyol component other than the polyol (a1) having a bisphenol skeleton structure may be a low molecular weight polyol having no bisphenol skeleton structure but having an aromatic structure, and a low molecular weight polyol having no aromatic structure. It may be.

Examples of low molecular weight polyols having no aromatic structure include ethylene glycol, diethylene glycol, triethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexane. Diol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,2-propylene glycol , Dipropylene glycol, tripropylene glycol, 1,3-butanediol, 1,2-butanediol, 2,3-butanediol, 1,5-hexanediol, 2,5-hexanediol, 2-methyl-1, 3-Propanediol, 2,2-dimethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2-ethyl-1, 3-Hexanediol, 2-Methyl-1,8-octanediol, 1,4-Cyclohexanediol, 1,4-Cyclohexanedimethanol, 1,2-propylene glycol, Dipropylene glycol, Tripropylene glycol, 1,3- Butanediol, 1,2-butanediol, 2,3-butanediol, 1,-hexanediol, 2,5-hexanediol, 2-ethyl-1,3-hexanediol, 2-methyl-1,8-octane Diol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 3-methyl-1,5-pentane Examples thereof include diols and trimethylol propane.

<Dispersion of resin>
The ink resin according to one aspect of the present invention is preferably used in the state of a dispersion (resin emulsion) in which the ink resin is dispersed in an aqueous medium. Such a dispersion can be suitably used as a binder for ink.

Examples of the method for dispersing the resin in the aqueous medium include a forced emulsification method using a dispersant and a self-emulsification method using a resin containing a hydrophilic group. Above all, the self-emulsifying method is preferable because it does not use a dispersant and therefore the dispersant does not remain in the coating film, so that the strength of the coating film is not lowered.

As described above, the resin for ink may be a polyurethane resin, and the polyurethane resin contains a polymer polyol component (A), a short-chain polyol component (B), a polyisocyanate component (C), and if necessary, chains. It may be a polyurethane resin obtained by reacting with an extender (D). Here, the polyurethane resin can contain a hydrophilic group by a self-emulsifying method, and the content of the hydrophilic group can be achieved by including the hydrophilic group-containing polyol in the short-chain polyol component (B). ..

Examples of the hydrophilic group-containing polyol include an anionic group, a cationic group, and a nonionic group, and it is preferable to use an anionic group among these.

Examples of the anionic group include a carboxyl group and a sulfonic acid group.

Examples of the method for introducing an anionic group into the urethane resin include the use of a polyol having an anionic group, and examples of the polyol having an anionic group include 2,2-dimethylolpropionic acid and 2,2. -Dimethylolbutanoic acid, 2,2-dimethylolheptanic acid, 2,2-dimethyloloctanoic acid and the like can be mentioned.

It is preferable that the anionic group is partially or wholly, particularly preferably wholly, neutralized by a neutralizing agent.

Examples of the neutralizing agent that can be used for neutralizing the anionic group include organic amines such as ammonia, triethylamine, pyridine and morpholin, basic compounds such as alkanolamines such as monoethanolamine, and Na, K and Li. , Ca and the like containing metal base compounds and the like.

As a composition ratio, [the number of moles of the hydrophilic group-containing polyol / (the number of moles of the polymer polyol component (A) + the number of moles of the short-chain polyol component (B))] is 0.15 or more and 0.45 or less. Is more preferable, 0.15 or more and 0.4 or less is more preferable, and 0.17 or more and 0.35 or less is particularly preferable. Here, the "number of moles of the polymer polyol component (A)" is a value based on the molecular weight derived from the hydroxyl value.

Within the above range, the polyurethane resin can be satisfactorily dispersed in the aqueous solvent, so that an ink having excellent storage stability and ejection stability can be obtained. Further, since a polyurethane resin having appropriate hydrophilicity can be formed, it is possible to obtain an ink capable of forming an image having excellent water resistance and solvent resistance.

When the short-chain polyol component (B) is composed of a hydrophilic group-containing polyol, the above value indicates [the number of moles of the hydrophilic group-containing polyol / (the number of moles of the polymer polyol component (A) + the content of the hydrophilic group). The number of moles of the polyol)].

In addition to the hydrophilic group-containing polyol, the short-chain polyol component (B) can contain (mix) a polyol that does not contain a hydrophilic group, if necessary.

Examples of polyols that do not contain hydrophilic groups include ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, and 1,8-octanediol. Examples thereof include 1,4-cyclohexanedimethanol, diethylene glycol, glycerin, and trimethylolpropane.

<Polyisocyanate>
Examples of the polyisocyanate (C) include 1,3-phenylenediocyanate, 1,4-phenylenediocyanate, 2,4-tolylene diisocyanate (TDI), 2,6-tolylene diisocyanate, and 4,4'-diphenylmethane. Diisocyanate (MDI), 2,4-diphenylmethane diisocyanate, 4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4' -Aromas such as diisocyanatodiphenylmethane, 1,5-naphthylene diisocyanate, 4,4,4', 4''-triphenylmethane triisocyanate, m-isocyanatophenylsulfonylisocyanate, p-isocyanatophenylsulfonylisocyanate Polyisocyanate compounds; ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 1,6,11-undecantryisocyanate, 2,2,4-trimethylhexamethylenediisocyanate, lysine diisocyanate, 2,6- Aliphatic polyisocyanate compounds such as diisocyanatomethyl caproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanatohexanoate Isophorone diisocyanate (IPDI), 4,4'-dicyclohexylmethane diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), bis (2-isocyanatoethyl) -4-diclohexene-1, Examples thereof include alicyclic polyisocyanate compounds such as 2-dicarboxylate, 2,5-norbornandiisocyanate, and 2,6-norbornandiisocyanate. These may be used alone or in combination of two or more.

Among these, an aliphatic polyisocyanate compound and an alicyclic polyisocyanate compound are preferable, and an alicyclic polyisocyanate compound is more preferable, isophorone diisocyanate and 4), because the color development of the image does not decrease due to yellowing over time. , 4'-Dicyclohexylmethane diisocyanate is particularly preferred.

The value of the number of moles of the isocyanate group derived from the polyisocyanate component (C) with respect to the number of moles of the hydroxyl group derived from the polymer polyol component (A) and the short chain polyol component (B), that is, the constituent ratio is [polyisocyanate component (C). The number of moles of the isocyanate group derived from) / the number of moles of the hydroxyl group derived from the polymer polyol component (A) and the short-chain polyol component (B)] is preferably 1.05 or more and 1.4 or less, and 1.05 or more and 1 .3 or less is more preferable, and 1.1 or more and 1.25 or less is particularly preferable.

Within the above range, a urethane resin capable of forming an image having excellent abrasion resistance and blocking resistance can be obtained.

Examples of the chain extender (D) include polyamines.

Examples of polyamines include ethylenediamine, 1,2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2,5-dimethylpiperazin, isophoronediamine, 4,4'-dicyclohexylmethanediamine, and 1,4-cyclohexanediamine. Diamines such as; polyamines such as diethylenetriamine, dipropylenetriamine, triethylenetetramine; hydrazines such as hydrazine, N, N'-dimethylhydrazine, 1,6-hexamethylenebishydrazine; dihydrazide succinate, dihydrazide adipic acid, etc. Examples thereof include dihydrazides such as glutarate dihydrazide, sebacic acid dihydrazide, and isophthalic acid dihydrazide.

It is particularly preferable to use a trifunctional polyamine as the polyamine. This makes it possible to obtain a urethane resin capable of forming an image having excellent solvent resistance.

<Other characteristics of urethane resin>
The glass transition temperature (Tg) of the urethane resin may be 35 ° C. or higher, and may be 40 ° C. or higher. Within the above range, an ink having good scratch resistance, blocking resistance, storage stability, and ejection stability can be obtained. The glass transition temperature (Tg) of the urethane resin is preferably 70 ° C. or higher, preferably 80 ° C. or higher, and more preferably 80 ° C. or higher and 120 ° C. or lower. Within the above range, it is possible to obtain an ink capable of forming an image having particularly excellent abrasion resistance and blocking resistance.

The glass transition temperature of the urethane resin can be measured using, for example, a differential scanning calorimeter (TA-60WS and DSC-60, manufactured by Shimadzu Corporation). First, 4 g of ink is uniformly spread in a PFA petri dish having a diameter of 50 mm, dried at 40 ° C. for 1 week, and then 5.0 mg of the obtained ink film is placed in an aluminum sample container, and the sample container is placed in a holder unit. Place on and set in an electric furnace. Then, in a nitrogen atmosphere, the temperature is raised from 0 ° C. to 150 ° C. at a heating rate of 10 ° C./min, then lowered from 150 ° C. to -80 ° C. at a temperature lowering rate of 5 ° C./min, and then further heated to 10 ° C. The temperature is raised to 150 ° C. at / min and the DSC curve is measured.

From the obtained DSC curve, the glass transition temperature (Tg) can be obtained by analyzing the inflection point at the time of the second temperature rise by the midpoint method using the analysis program in the DSC-60 system.

The acid value of the urethane resin is preferably 10 mgKOH / g or more and 40 mgKOH / g or less. Within the above range, a urethane resin capable of forming an ink having good dispersion stability can be obtained.

The acid value of the urethane resin can be measured, for example, by putting the urethane resin in a tetrahydrofuran (THF) solution and titrating it with a 0.1 M potassium hydroxide methanol solution. it can.

<Ink>
According to one aspect of the present invention, the ink may contain the above-mentioned ink resin. Further, the ink may contain an ink resin, a coloring material, water, an organic solvent, and may optionally contain an additive. Hereinafter, the organic solvent, water, coloring material, additives 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 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-hexanediol, ethyl-1,2,4-butanetriol, 1,2,3-butanetriol, 2,2,4-trimethyl- Polyhydric alcohols such as 1,3-pentanediol and petriol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol monoethyl Polyhydric alcohol alkyl ethers such as ether, polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone. , 1,3-Dimethyl-2-imidazolidinone, ε-caprolactam, γ-butyrolactone and other nitrogen-containing heterocyclic compounds, formamide, N-methylformamide, N, N-dimethylformamide, 3-methoxy-N, N- Amidos such as dimethylpropionamide, 3-butoxy-N, N-dimethylpropionamide, amines such as monoethanolamine, diethanolamine and triethylamine, sulfur-containing compounds such as dimethylsulfoxide, sulfolane and thiodiethanol, propylene carbonate and ethylene carbonate. And so on.

It is preferable to use an organic solvent having a boiling point of 250 ° C. or lower because it not only functions as a wetting agent but also has good drying properties.

Polyol compounds having 8 or more carbon atoms and glycol ether compounds are also preferably used. Specific examples of the polyol compound having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol and 2,2,4-trimethyl-1,3-pentanediol.

Specific examples of the glycol ether compound include polyvalent 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. Ethers: Polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether can be mentioned.

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

The content of the organic solvent 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 60% by mass or less from the viewpoint of ink drying property and ejection reliability. More preferably, it is 20% by mass or more and 60% by mass or less.

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

<Color material>
The coloring material is not particularly limited, and pigments and dyes can be used.

As the pigment, an inorganic pigment or an organic pigment can be used. These may be used alone or in combination of two or more. Moreover, you may use a mixed crystal.

As the pigment, for example, black pigment, yellow pigment, magenta pigment, cyan pigment, white pigment, green pigment, orange pigment, glossy color pigment such as gold or silver, metallic pigment and the like can be used.

As inorganic pigments, in addition to titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, and chrome yellow, carbon black produced by known methods such as contact method, furnace method, and thermal method. Can be used.

Examples of organic pigments include azo pigments and polycyclic pigments (for example, phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, quinofuralone pigments, etc.). , Dye chelate (for example, basic dye type chelate, acidic dye type chelate, etc.), nitro pigment, nitroso pigment, aniline black and the like can be used. Among these pigments, those having a good affinity with a solvent are preferably used. In addition, resin hollow particles and inorganic hollow particles can also be used.

As a specific example of the pigment, for black, carbon black (CI pigment black 7) such as furnace black, lamp black, acetylene black, channel black, or copper, iron (CI pigment black 11) , Metals such as titanium oxide, and organic pigments such as aniline black (CI pigment black 1).

Further, for color, 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 Carmin 6B), 60: 1, 63: 1, 63: 2, 64: 1, 81, 83, 88, 101 (Magenta), 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 Greens 1, 4, 7, 8, 10, 17, 18, 36, etc.

The dye is not particularly limited, and acid dyes, direct dyes, reactive dyes, and basic dyes can be used, and one type may be used alone or two or more types may be used in combination.

As the dye, for example, 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. Hood 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. Dilekdo 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, 35 can be mentioned.

The content of the coloring 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 viewpoint of improving image density, good fixability and ejection stability. It is as follows.

To disperse the pigment in the ink, a method of introducing a hydrophilic functional group into the pigment to obtain a self-dispersing pigment, a method of coating the surface of the pigment with a resin and dispersing the pigment, a method of dispersing using a dispersant, And so on.

Examples of the method of introducing a hydrophilic functional group into a pigment to obtain a self-dispersing pigment include a self-dispersing pigment in which a functional group such as a sulfone group or a carboxyl group is added to a pigment (for example, carbon) so that the pigment can be dispersed in water. Can be used.

As a method of coating the surface of the pigment with a resin and dispersing it, a method in which the pigment is encapsulated in microcapsules and can be dispersed in water can be used. This can be rephrased as a resin coating pigment. In this case, it is not necessary that all the pigments to be blended in the ink are coated with the resin, and the uncoated pigments and the partially coated pigments are dispersed in the ink as long as the effects of the present invention are not impaired. You may be.

Examples of the method of dispersing using a dispersant include a method of dispersing using a known low-molecular-weight dispersant and high-molecular-weight dispersant represented by a surfactant.

As the dispersant, for example, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant and the like can be used depending on the pigment.

RT-100 (nonionic surfactant) manufactured by Takemoto Oil & Fat Co., Ltd. and a naphthalene sulfonate Na formalin condensate can also be suitably used as a dispersant.

The dispersant may be used alone or in combination of two or more.

<Pigment dispersion>
It is possible to obtain ink by mixing a material such as water or an organic solvent with a coloring material. It is also possible to produce an ink by mixing a material such as water or an organic solvent with a pigment dispersion obtained by mixing a pigment and other water or a dispersant.

The pigment dispersion is obtained by dispersing water, a pigment, a pigment dispersant, and other components as necessary, and adjusting the particle size. It is preferable to use a disperser for dispersion.

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 the maximum number because the dispersion stability of the pigment is good and the image quality such as ejection stability and image density is also high. It is preferably 500 nm or less, more preferably 20 nm or more and 150 nm or less. The particle size of the pigment can be measured using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrac 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 mass is used. % Or more and 50% by mass or less are preferable, and 0.1% by mass or more and 30% by mass or less are more preferable.

It is preferable that the pigment dispersion is degassed by filtering coarse particles with a filter, a centrifuge, or the like, if necessary.

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

<Surfactant>
As the surfactant, any of a silicone-based surfactant, a fluorine-based surfactant, an amphoteric surfactant, a nonionic surfactant, and an anionic surfactant can be used.

The silicone-based surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. Among them, those that do not decompose even at high pH are preferable, and examples thereof include side chain modified polydimethylsiloxane, double-ended modified polydimethylsiloxane, one-ended modified polydimethylsiloxane, and side chain double-ended modified polydimethylsiloxane. Those having an oxyethylene group and a polyoxyethylene polyoxypropylene group are particularly preferable because they exhibit good properties as an aqueous surfactant. Further, as the silicone-based surfactant, a polyether-modified silicone-based surfactant can also be used, and examples thereof include a compound in which a polyalkylene oxide structure is introduced into the Si side chain of dimethylsiloxane.

Examples of the fluorine-based surfactant 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. A polyoxyalkylene ether polymer compound is particularly preferable because it has a low foaming property. Examples of the perfluoroalkyl sulfonic acid compound include perfluoroalkyl sulfonic acid and perfluoroalkyl sulfonic acid salt. Examples of the perfluoroalkylcarboxylic acid compound include perfluoroalkylcarboxylic acid and perfluoroalkylcarboxylic acid salt. The polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain includes 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. The counterions of the salts in these fluorine-based surfactants are 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). _3rd grade can be mentioned.

Examples of the amphoteric tenside agent include laurylaminopropionate, lauryldimethylbetaine, stearyldimethylbetaine, and lauryldihydroxyethylbetaine.

Examples of the nonionic surfactant include polyoxyethylene alkylphenyl ether, polyoxyethylene alkyl ester, polyoxyethylene alkyl amine, polyoxyethylene alkyl amide, polyoxyethylene propylene block polymer, sorbitan fatty acid ester, and polyoxyethylene sorbitan. Examples thereof include ethylene oxide adducts of fatty acid esters and acetylene alcohols.

Examples of the anionic surfactant include polyoxyethylene alkyl ether acetate, dodecylbenzene sulfonate, lauryl salt, polyoxyethylene alkyl ether sulfate salt and the like.

These may be used alone or in combination of two or more.

The silicone-based surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, side chain-modified polydimethylsiloxane, double-ended modified polydimethylsiloxane, one-ended modified polydimethylsiloxane, side. Examples thereof include polydimethylsiloxane modified at both ends of the chain, and a polyether-modified silicone-based surfactant having a polyoxyethylene group and a polyoxyethylene polyoxypropylene group as modifying groups exhibits good properties as an aqueous surfactant, and is particularly effective. preferable.

As such a surfactant, an appropriately synthesized one may be used, 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., Kyoeisha Chemical Co., Ltd.

The above-mentioned polyether-modified silicone-based surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the polyalkylene oxide structure represented by the general formula (S-1) is dimethylpoly. Examples thereof include those introduced into the Si part side chain of siloxane.

（但し、一般式（Ｓ−１）式中、ｍ、ｎ、ａ、及びｂは整数を表わす。Ｒ及びＲ'はアルキル基、アルキレン基を表わす。）
上記のポリエーテル変性シリコーン系界面活性剤としては、市販品を用いることができ、例えば、ＫＦ−６１８、ＫＦ−６４２、ＫＦ−６４３（信越化学工業株式会社）、ＥＭＡＬＥＸ−ＳＳ−５６０２、ＳＳ−１９０６ＥＸ（日本エマルジョン株式会社）、ＦＺ−２１０５、ＦＺ−２１１８、ＦＺ−２１５４、ＦＺ−２１６１、ＦＺ−２１６２、ＦＺ−２１６３、ＦＺ−２１６４（東レ・ダウコーニング・シリコーン株式会社）、ＢＹＫ−３３、ＢＹＫ−３８７（ビックケミー株式会社）、ＴＳＦ４４４０、ＴＳＦ４４５２、ＴＳＦ４４５３（東芝シリコン株式会社）などが挙げられる。

(However, in the general formula (S-1), m, n, a, and b represent integers. R and R'represent an alkyl group and an alkylene group.)
Commercially available products can be used as the above-mentioned polyether-modified silicone-based surfactant, for example, KF-618, KF-642, KF-643 (Shinetsu Chemical Industry Co., Ltd.), EMALEX-SS-5602, SS- 1906EX (Nippon 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 (Big Chemie Co., Ltd.), TSF4440, TSF4452, TSF4453 (Toshiba Silicon Co., Ltd.) and the like can be mentioned.

As the fluorine-based surfactant, a compound having 2 to 16 carbon atoms substituted with fluorine is preferable, and a compound having 4 to 16 carbon atoms substituted with fluorine is more preferable.

Examples of the fluorine-based surfactant include a perfluoroalkyl phosphate compound, a perfluoroalkylethylene oxide adduct, and a polyoxyalkylene ether polymer compound 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 preferable because they have low foaming property, and are particularly fluorine-based compounds represented by the general formulas (F-1) and (F-2). Surfactants are preferred.

上記一般式（Ｆ−１）において、水溶性を付与するためにｍは０〜１０の整数が好ましく、ｎは０〜４０の整数が好ましい。

In the above 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.

上記一般式（Ｆ−２）において、ＹはＨ、又はＣｎＦ_２ｎ＋１であり、ｎは1〜６の整数、又はＣＨ_２ＣＨ（ＯＨ）ＣＨ_２−ＣｎＦ_２ｎ＋１であり、ｎは４〜６の整数、又はＣｐＨ_２ｐ＋１であり、ｐは１〜１９の整数である。ａは４〜１４の整数である。

In the above general formula (F-2), Y is H or CnF _{2n + 1} , n is an integer of 1 to 6, or CH ₂ CH (OH) CH _2- CnF _{2n + 1} , and n is an integer of 4 to 6. , Or CpH _{2p + 1} , where p is an integer of 1-19. a is an integer of 4 to 14.

Commercially available products may be used as the above-mentioned fluorine-based surfactant. Examples of this commercially available product include Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, and S-145 (all manufactured by Asahi Glass Co., Ltd.); Full Lard FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, FC-431 (all manufactured by Sumitomo 3M Co., Ltd.); Megafuck F-470, F -1405, F-474 (all manufactured by Dainippon Ink and Chemicals Co., Ltd.); Zonyl TBS, FSP, FSA, FSN-100, FSN, FSO-100, FSO, FS-300, UR (all) , DuPont); FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW (all manufactured by Neos Co., Ltd.), Polyfox PF-136A, PF-156A, PF-151N, PF-154, PF-159 (manufactured by Omniova), Unidyne DSN-403N (manufactured by Daikin Industries, Ltd.), etc. Among these, good print quality, especially color development and permeability to paper. FS-300 manufactured by DuPont, FT-110, FT-250, FT-251, FT-400S, FT-150, FT- of Neos Co., Ltd. from the viewpoint of remarkably improving wettability and leveling property. 400SW, Polyfox PF-151N manufactured by Omniova Co., Ltd. and Unidyne DSN-403N manufactured by Daikin Industries, Ltd. are particularly preferable.

The content of the surfactant in the ink is not particularly limited and may be appropriately selected depending on the intended purpose. However, 0.001 mass is obtained from the viewpoint of excellent wettability and ejection stability and improvement in image quality. % Or more and 5% by mass or less are preferable, and 0.05% by mass or more and 5% by mass or less are more preferable.

<Defoamer>
The defoaming agent is not particularly limited, and examples thereof include a silicone-based defoaming agent, a polyether-based defoaming agent, and a fatty acid ester-based defoaming agent. These may be used alone or in combination of two or more. Among these, a silicone-based defoaming agent is preferable because it has an excellent defoaming effect.

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

<Rust inhibitor>
The rust preventive is not particularly limited, and examples thereof include acidic sulfites and sodium thiosulfate.

<pH adjuster>
The pH adjusting agent 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.

<Physical characteristics of ink>
The physical characteristics of the ink are not particularly limited and may be appropriately selected depending on the intended purpose. For example, the viscosity, surface tension, pH and the like are preferably in the following ranges.

The viscosity of the ink at 25 ° C. 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 print density and character quality and obtaining good ejection properties. More preferred. Here, for the viscosity, for example, a rotary viscometer (RE-80L manufactured by Toki Sangyo Co., Ltd.) can be used. As the measurement conditions, it is possible to measure at 25 ° C. with a standard cone rotor (1 ° 34'x R24), a sample liquid volume of 1.2 mL, a rotation speed of 50 rpm, and 3 minutes.

The surface tension of the ink is preferably 35 mN / m or less, more preferably 32 mN / m or less at 25 ° C. from the viewpoint that the ink is preferably leveled on the recording medium and the drying time of the ink is shortened.

The pH of the ink is preferably 7 to 12, 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 used for recording is not particularly limited, and examples thereof include plain paper, glossy paper, special paper, film, OHP sheet, and general-purpose printing paper. Specific examples include a coated recording medium, for example, coated paper for commercial use, and a recording medium such as a continuous form that is wound up on a roll again after printing.

<Recorded material>
An ink recording material according to one aspect of the present invention comprises an image formed by using the ink of the present invention on a recording medium.

It can be recorded by an inkjet recording device and an inkjet recording method to obtain a recorded material.

<Manufacturing method of resin for ink>
According to one aspect of the present invention, which is a method for producing a resin for ink, a polyester polyol is obtained by subjecting a bisphenol compound and a polycarboxylic acid to a condensation reaction, and the polyester polyol is reacted with a polyisocyanate to obtain the above. A method can be provided that comprises obtaining a polyurethane resin.

Further, according to one aspect of the present invention, in the method for producing a resin for ink, a polyester polyol is obtained by subjecting a bisphenol compound and a polycarboxylic acid to a condensation reaction, and the polyester polyol, the polyisocyanate, and hydrophilicity are obtained. A method can be provided that comprises reacting with a group-containing polyol to obtain the polyurethane resin.

In the step of obtaining a polyester polyol by subjecting the above-mentioned bisphenol compound to a polycarboxylic acid in a condensation reaction, a mixture of the bisphenol compound and the polycarboxylic acid is melted while introducing an inert gas, and the mixture is reacted at a predetermined temperature. This can be done by stopping the introduction of the active gas and then further reacting under reduced pressure.

<Recording device, recording method>
The ink of the present invention can be suitably used for various recording devices by an inkjet recording method, for example, a printer, a facsimile device, a copying device, a printer / fax / copier multifunction device, a three-dimensional modeling device, and the like.

In the present application, the recording device and the recording method include a device capable of ejecting ink, various processing liquids, and the like to a recording medium, and a method of recording using the device. That is, it is a method in which droplets of ink or various treatment liquids are ejected from a nozzle of an ejection head and applied to a recording medium for recording. The recording medium means a medium to which ink and various treatment liquids can adhere even temporarily.

This recording device can include not only a head portion for ejecting ink, but also means related to feeding, transporting, and discharging paper of a recording medium, and other devices called pretreatment devices and posttreatment devices. ..

The recording device and recording method may include a heating means used in the heating step and a drying means used in the drying step. The heating means and the drying means include, for example, means for heating and drying the print surface and the back surface of the recording medium. The heating means and the drying means are not particularly limited, but for example, a hot 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 device and the recording method are not limited to those in which significant images such as characters and figures are visualized by ink. For example, those that form patterns such as geometric patterns and those that form a three-dimensional image are also included.

Further, the recording device includes both a serial type device that moves the discharge head and a line type device that does not move the discharge head, unless otherwise specified.

Further, as this recording device, it is possible to use not only a desktop type but also a wide recording device capable of printing on an A0 size recording medium, or, for example, continuous paper wound in a roll shape as a recording medium. A continuous line printer is also included.

An example of the recording device will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective explanatory view of the device. FIG. 2 is a perspective explanatory view of the main tank. The image forming apparatus 400 as an example of the recording apparatus is a serial type image forming apparatus. A mechanical unit 420 is provided in the exterior 401 of the image forming apparatus 400. Each ink container 411 of the main tank 410 (410k, 410c, 410m, 410y) for each color of black (K), cyan (C), magenta (M), and yellow (Y) is packaged with, for example, an aluminum laminate film. It is formed of members. The ink storage unit (ink storage container) 411 is housed in, for example, a plastic storage 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 behind the opening when the cover 401c of the main body of the apparatus is opened. A main tank 410 is detachably attached to the cartridge holder 404. As a result, each ink discharge port 413 of the main tank 410 and the discharge head 434 for each color communicate with each other via the supply tube 436 for each color, and ink can be discharged from the discharge head 434 to the recording medium.

This recording device can include not only a portion that ejects ink, but also a device called a pretreatment device, a posttreatment device, and the like.

As one aspect of the pretreatment apparatus and the posttreatment apparatus, it has a pretreatment liquid and a posttreatment liquid as in the case of inks such as black (K), cyan (C), magenta (M), and yellow (Y). There is an embodiment in which a liquid accommodating portion and a liquid discharge head are added, and a pretreatment liquid or a posttreatment liquid is discharged by an inkjet recording method.

As another aspect of the pretreatment device and the posttreatment device, there is a mode in which a pretreatment device and a posttreatment device by, for example, a blade coating method, a roll coating method, and a spray coating method are provided other than the inkjet recording method.

The method of using the ink is not limited to the inkjet recording method, and can be widely used. In addition to the inkjet recording method, examples thereof include 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, and a spray coating method.

The use of the ink of the present invention is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it can be applied to printed matter, paints, coating materials, base materials and the like. Further, it can be used not only as an ink to form two-dimensional characters and images, but also as a three-dimensional modeling material for forming a three-dimensional three-dimensional image (three-dimensional model).

A known three-dimensional modeling device can be used for modeling the three-dimensional object, and the device is not particularly limited, but for example, an device provided with ink accommodating means, supply means, ejection means, drying means, and the like is used. be able to. The three-dimensional model includes a three-dimensional model obtained by overcoating with ink. In addition, a molded product obtained by processing a structure in which ink is applied on a base material such as a recording medium is also included. The molded product is, for example, a recorded material or structure formed in the form of a sheet or a film, which has been subjected to molding processing such as heat stretching or punching. For example, an automobile, an OA device, or an electric machine. -Suitably used for molding after decorating the surface of electronic devices, meters of cameras, panels of operation parts, etc.

Examples of the present invention will be described below, but the present invention is not limited to these examples.

<Example 1>
[Synthesis of polyester polyol 1]
While introducing nitrogen into a 0.5 L separable flask, 343 g of BA-2 (an ethylene oxide adduct of bisphenol A; manufactured by Nippon Emulsifier Co., Ltd.) and 137 g of dimethyl isophthalate were charged and melted at 130 ° C. When these were melted, 0.14 g of titanium tetraisopropoxide was added, the temperature was raised to 230 ° C. over 3 to 4 hours with stirring, and the reaction was carried out at 230 ° C. for another 2 to 3 hours. Then, 0.07 g of titanium tetraisopropoxide was added and held for 2 hours, nitrogen introduction was stopped, and the reaction was carried out under a reduced pressure of 1 kPa for another 2 hours to obtain a polyester polyol 1. The obtained polyester polyol 1 had a number average molecular weight of 1646 and a hydroxyl value of 95.6 mgKOH / g.

[Synthesis of urethane resin emulsion 1]
Polyester polyol 1 100 g, 2,2-bis (hydroxymethyl) propionic acid (2,2-dimethylolpropion) while introducing nitrogen into a 0.5 L separable flask equipped with a stirring blade, a thermometer, and a reflux tube. 5.4 g of acid), 4.1 g of triethylamine, and 78 g of acetone were charged and heated to 40 ° C. to dissolve the raw materials. Then, 35 g of isophorone diisocyanate and 1 drop of 2-ethylhexanoic acid tin (II) were added, the temperature was raised to 80 ° C., and the reaction was carried out for 4 hours. Then, the temperature was lowered to 40 ° C., 268 g of water was added to form fine particles, and 2.3 g of diethylenetriamine was further added, and the mixture was reacted for 4 hours. Finally, by removing acetone, a urethane resin emulsion 1 having a solid content concentration of 32% by mass was obtained.

<Example 2>
[Synthesis of polyester polyol 2]
While introducing nitrogen into a 0.5 L separable flask, 343 g of BA-2 (an ethylene oxide adduct of bisphenol A; manufactured by Nippon Emulsifier Co., Ltd.) and 137 g of dimethyl terephthalate were charged and melted at 130 ° C. When these were melted, 0.14 g of titanium tetraisopropoxide was added, the temperature was raised to 230 ° C. over 3 to 4 hours with stirring, and the reaction was carried out at 230 ° C. for another 2 to 3 hours. Then, 0.07 g of titanium tetraisopropoxide was added and held for 2 hours, nitrogen introduction was stopped, and the reaction was carried out under a reduced pressure of 1 kPa for another 2 hours to obtain a polyester polyol 2. The obtained polyester polyol 2 had a number average molecular weight of 1615 and a hydroxyl value of 93.4 mgKOH / g.

[Synthesis of urethane resin emulsion 2]
While introducing nitrogen into a 0.5 L separable flask equipped with a stirring blade, a thermometer, and a reflux tube, 100 g of polyester polyol, 5.5 g of 2,2-bis (hydroxymethyl) propionic acid, and 4.1 g of triethylamine. , 78 g of acetone was charged and heated to 40 ° C. to dissolve the raw materials. Then, 35 g of isophorone diisocyanate and 1 drop of 2-ethylhexanoic acid tin (II) were added, the temperature was raised to 80 ° C., and the reaction was carried out for 4 hours. Then, the temperature was lowered to 40 ° C., 269 g of water was added to form fine particles, and 2.3 g of diethylenetriamine was further added to react for 4 hours. Finally, by removing acetone, a urethane resin emulsion 2 having a solid content concentration of 32% by mass was obtained.

<Example 3>
[Synthesis of polyester polyol 3]
While introducing nitrogen into a 0.5 L separable flask, 323 g of BA-2 (an ethylene oxide adduct of bisphenol A; manufactured by Nippon Emulsifier Co., Ltd.), 14.8 g of trimethylolpropane, and 143 g of dimethyl isophthalate were charged, and 130 Melted at ° C. When these were melted, 0.14 g of titanium tetraisopropoxide was added, the temperature was raised to 230 ° C. over 3 to 4 hours with stirring, and the reaction was carried out at 230 ° C. for another 2 to 3 hours. Then, 0.07 g of titanium tetraisopropoxide was added and held for 2 hours, nitrogen introduction was stopped, and the reaction was carried out under a reduced pressure of 1 kPa for another 2 hours to obtain a polyester polyol 3. The obtained polyester polyol 3 had a number average molecular weight of 1506 and a hydroxyl value of 101 mgKOH / g.

[Synthesis of urethane resin emulsion 3]
While introducing nitrogen into a 0.5 L separable flask equipped with a stirring blade, a thermometer and a reflux tube, 100 g of polyester polyol 3, 5.7 g of 2,2-bis (hydroxymethyl) propionic acid, and 4.3 g of triethylamine. , 79 g of acetone was charged and heated to 40 ° C. to dissolve the raw materials. Then, 37 g of isophorone diisocyanate and 1 drop of 2-ethylhexanoic acid tin (II) were added, the temperature was raised to 80 ° C., and the reaction was carried out for 4 hours. Then, the temperature was lowered to 40 ° C., 273 g of water was added to form fine particles, and 2.2 g of diethylenetriamine was further added and reacted for 4 hours. Finally, by removing acetone, a urethane resin emulsion 3 having a solid content concentration of 31% by mass was obtained.

<Example 4>
[Synthesis of polyester polyol 4]
While introducing nitrogen into a 0.5 L separable flask, 407 g of BA-2 (an ethylene oxide adduct of bisphenol A; manufactured by Nippon Emulsifier Co., Ltd.) and 73 g of dimethyl adipate were charged and melted at 130 ° C. When these were melted, 0.14 g of titanium tetraisopropoxide was added, the temperature was raised to 230 ° C. over 3 to 4 hours with stirring, and the reaction was carried out at 230 ° C. for another 2 to 3 hours. Then, 0.07 g of titanium tetraisopropoxide was added and held for 2 hours, nitrogen introduction was stopped, and the reaction was carried out under a reduced pressure of 1 kPa for another 2 hours to obtain a polyester polyol 4. The obtained polyester polyol 4 had a number average molecular weight of 1450 and a hydroxyl value of 110 mgKOH / g.

[Urethane resin emulsion 4]
While introducing nitrogen into a 0.5 L separable flask equipped with a stirring blade, a thermometer, and a reflux tube, 100 g of polyester polyol, 5.4 g of 2,2-bis (hydroxymethyl) propionic acid, and 4.1 g of triethylamine. , 78 g of acetone was charged and heated to 40 ° C. to dissolve the raw materials. Then, 35 g of isophorone diisocyanate and 1 drop of 2-ethylhexanoic acid tin (II) were added, the temperature was raised to 80 ° C., and the reaction was carried out for 4 hours. Then, the temperature was lowered to 40 ° C., 268 g of water was added to form fine particles, and 2.3 g of diethylenetriamine was further added, and the mixture was reacted for 4 hours. Finally, by removing acetone, a urethane resin emulsion 4 having a solid content concentration of 32% by mass was obtained.

<Comparative example 1>
[Synthesis of polyester polyol 5]
170 g of propylene glycol and 310 g of dimethyl terephthalate were charged into a 0.5 L separable flask while introducing nitrogen, and melted at 130 ° C. When these were melted, 0.14 g of titanium tetraisopropoxide was added, the temperature was raised to 230 ° C. over 3 to 4 hours with stirring, and the reaction was carried out at 230 ° C. for another 2 to 3 hours. Then, 0.07 g of titanium tetraisopropoxide was added and held for 2 hours, nitrogen introduction was stopped, and the reaction was carried out under reduced pressure of 15 kPa for another 3 hours to obtain a polyester polyol. The obtained polyester polyol 5 had a number average molecular weight of 1699 and a hydroxyl value of 92.3 mgKOH / g.

[Synthesis of Urethane Resin Emulsion 5]
While introducing nitrogen into a 0.5 L separable flask equipped with a stirring blade, a thermometer and a reflux tube, 100 g of polyester polyol 5, 5.2 g of 2,2-bis (hydroxymethyl) propionic acid, and 2.7 g of triethylamine. , 76 g of acetone was charged and heated to 40 ° C. to dissolve the raw materials. Then, 34 g of isophorone diisocyanate and 1 drop of 2-ethylhexanoic acid tin (II) were added, the temperature was raised to 80 ° C., and the reaction was carried out for 4 hours. Then, the temperature was lowered to 40 ° C., 263 g of water was added to form fine particles, and 2.1 g of diethylenetriamine was further added to react for 4 hours. Finally, by removing acetone, a urethane resin emulsion 5 having a solid content concentration of 33% by mass was obtained.

<Comparative example 2>
[Synthesis of polyester polyol 6]
While introducing nitrogen into a 0.5 L separable flask, 177 g of propylene glycol, 129 g of dimethyl terephthalate, and 174 g of dimethyl adipate were charged and melted at 130 ° C. When these were melted, 0.14 g of titanium tetraisopropoxide was added, the temperature was raised to 230 ° C. over 3 to 4 hours with stirring, and the reaction was carried out at 230 ° C. for another 2 to 3 hours. Then, 0.07 g of titanium tetraisopropoxide was added and held for 2 hours, nitrogen introduction was stopped, and the reaction was carried out under reduced pressure of 15 kPa for another 2 hours to obtain a polyester polyol. The obtained polyester polyol 6 had a number average molecular weight of 1365 and a hydroxyl value of 128 mgKOH / g.

[Synthesis of urethane resin emulsion 6]
While introducing nitrogen into a 0.5 L separable flask equipped with a stirring blade, a thermometer, and a reflux tube, 100 g of polyester polyol 6, 6.2 g of 2,2-bis (hydroxymethyl) propionic acid, and 3.3 g of triethylamine. , 81 g of acetone was charged and heated to 40 ° C. to dissolve the raw materials. Then, 41 g of isophorone diisocyanate and 1 drop of 2-ethylhexanoic acid tin (II) were added, the temperature was raised to 80 ° C., and the reaction was carried out for 4 hours. Then, the temperature was lowered to 40 ° C., 278 g of water was added to form fine particles, and 2.3 g of diethylenetriamine was further added, and the mixture was reacted for 4 hours. Finally, by removing acetone, a urethane resin emulsion 6 having a solid content concentration of 31% by mass was obtained.

<Comparative example 3>
[Synthesis of polyester polyol 7]
While introducing nitrogen into a 0.5 L separable flask, 197 g of 2,2-dimethyl-1,3-propanediol and 283 g of dimethyl terephthalate were charged and melted at 130 ° C. When these were melted, 0.14 g of titanium tetraisopropoxide was added, the temperature was raised to 230 ° C. over 3 to 4 hours with stirring, and the reaction was carried out at 230 ° C. for another 2 to 3 hours. Then, 0.07 g of titanium tetraisopropoxide was added and held for 2 hours, nitrogen introduction was stopped, and the reaction was carried out under a reduced pressure of 1 kPa for another 2 hours to obtain a polyester polyol 7. The obtained polyester polyol 7 had a number average molecular weight of 1539 and a hydroxyl value of 110 mgKOH / g.

[Synthesis of urethane resin emulsion 7]
While introducing nitrogen into a 0.5 L separable flask equipped with a stirring blade, a thermometer, and a reflux tube, 100 g of polyester polyol 7, 5.7 g of 2,2-bis (hydroxymethyl) propionic acid, and 4.3 g of triethylamine. , 79 g of acetone was charged and heated to 40 ° C. to dissolve the raw materials. Then, 37 g of isophorone diisocyanate and 1 drop of 2-ethylhexanoic acid tin (II) were added, the temperature was raised to 80 ° C., and the reaction was carried out for 4 hours. Then, the temperature was lowered to 40 ° C., 273 g of water was added to form fine particles, and 2.3 g of diethylenetriamine was further added, and the mixture was reacted for 4 hours. Finally, by removing acetone, a urethane resin emulsion 7 having a solid content concentration of 32% by mass was obtained.

<Comparative example 4>
[Synthesis of polyester polyol 8]
While introducing nitrogen into a 0.5 L separable flask, 182 g of propylene glycol and 298 g of dimethyl adipate were charged and melted at 130 ° C. When these were melted, 0.14 g of titanium tetraisopropoxide was added, the temperature was raised to 230 ° C. over 3 to 4 hours with stirring, and the reaction was carried out at 230 ° C. for another 2 to 3 hours. Then, 0.07 g of titanium tetraisopropoxide was added and held for 2 hours, nitrogen introduction was stopped, and the reaction was carried out under reduced pressure of 15 kPa for another 2 hours to obtain a polyester polyol 8. The number average molecular weight was 1441 and the hydroxyl value was 125 mgKOH / g.

[Synthesis of urethane resin emulsion 8]
While introducing nitrogen into a 0.5 L separable flask equipped with a stirring blade, a thermometer, and a reflux tube, 100 g of polyester polyol 8, 6.5 g of 2,2-bis (hydroxymethyl) propionic acid, and 4.9 g of triethylamine. , 83 g of acetone was charged and heated to 40 ° C. to dissolve the raw materials. Then, 42 g of isophorone diisocyanate and 1 drop of 2-ethylhexanoic acid tin (II) were added, the temperature was raised to 80 ° C., and the mixture was reacted for 4 hours. Then, the temperature was lowered to 40 ° C., 285 g of water was added to form fine particles, and 2.4 g of diethylenetriamine was further added to react for 4 hours. Finally, by removing acetone, a urethane resin emulsion 8 having a solid content concentration of 31% by mass was obtained.

<Preparation of pigment dispersion>
The materials of the following formulations were mixed and further circulated and dispersed for 7 hours with a disc type bead mill (manufactured by Simmal Enterprises, KDL type, media: zirconia balls having a diameter of 0.3 mm) to obtain a pigment dispersion (pigment). Solid content 15% by mass).
-Pigment (Pigment Blue 15: 3): 15 parts by mass-Anionic surfactant (Pionin A-51-B, manufactured by Takemoto Oil & Fat Co., Ltd.): 2 parts by mass-Ion-exchanged water: 83 parts by mass

<Ink preparation>
Using the synthesized urethane resin emulsions 1 to 7, the materials were mixed and stirred according to the formulation shown in Table 1, and then filtered through a membrane filter having an average pore size of 0.8 μm to prepare an ink.

As the antiseptic and fungicide, Proxel LV manufactured by Abyssia Co., Ltd. was used. Further, as the surfactant, CH ₃ (CH ₂ ) ₁₂ O (CH ₂ CH ₂ O) ₃ CH ₂ COOH was used.

<Abrasion resistance>
Ink printers (IPSiO GX5000, manufactured by Ricoh Co., Ltd.) are filled with each ink so that the ink ejection amount becomes even in an environment adjusted to a temperature of 24 ± 0.5 ° C and a humidity of 50 ± 5% RH. The drive voltage of the piezo element is fluctuated, and a chart with a single-color solid printing part with an ink adhesion amount of 1 mg / cm ² is printed on gloss paper for printing (product name: LumiArtGloss with a basis weight of 90 g / m ² , manufactured by Enso, liquid absorbing liquid. Characteristics: Printed on a transfer amount of pure water 2.3 mL / m ² ) with a contact time of 100 ms, dried the printed image at 100 ° C for 30 seconds, and then cut into 1.1 cm square filter paper (product name: circular quantitative filter paper). # 5A 185 mm, manufactured by ADVANTEC) is attached to a clock meter (manufactured by Daiei Kagaku Seiki Seisakusho) using a polyurethane foam tape 4016 (manufactured by 3M) cut into 1 cm squares, and the printed part is printed with the pasted filter paper. The degree of rubbing and transfer of ink to the filter paper was visually observed and evaluated according to the following evaluation criteria. The results are summarized in Table 2.

[Evaluation criteria]
⊚: Transfer to filter paper is not observed ○: Slight transfer to filter paper is observed Δ: Transfer to filter paper is observed ×: Transfer to filter paper is remarkably observed. ○ or more is the allowable range.

<Blocking resistance>
Ink printers (IPSiO GX5000, manufactured by Ricoh Co., Ltd.) are filled with each ink so that the amount of ink ejected becomes even in an environment adjusted to a temperature of 24 ± 0.5 ° C and a humidity of 50 ± 5% RH. The drive voltage of the piezo element is fluctuated, and a chart with a single-color solid printing part with an ink adhesion amount of 1 mg / cm ² is printed on gloss paper for printing (product name: LumiArtGloss with a basis weight of 90 g / m ² , manufactured by Enso, liquid absorbing liquid. Characteristics: The transfer amount of pure water at a contact time of 100 ms was printed on 2.3 mL / m ² ), and then dried at 100 ° C. for 30 seconds. The same blank recording medium as that used for printing was placed on the printed image, a load of 5 kN was applied, the image was left for 24 hours, and then the adjacent surface was peeled off and evaluated according to the following criteria. The results are summarized in Table 3.

[Evaluation criteria]
⊚: Adjacent surface can be easily peeled off and there is no transfer to the blank paper side ○: Adjacent surface can be easily peeled off but slightly transferred to the blank paper side △: Adjacent surface is sticky and blank paper Transfer to the side is seen ×: Adjacent surface is sticky and transfer to the blank paper side is remarkable. ○ or more is the allowable range.

<Storage stability>
First, the viscosity (a) of the prepared ink was measured. Next, the prepared ink was placed in a Labran screw tube bottle, sealed tightly, and stored in an incubator at 70 ° C. for 2 weeks, and the viscosity (b) of the ink after storage was measured. The method for measuring the viscosity is as described above. From the viscosity (a) of the ink before storage and the viscosity (b) of the ink after storage, the viscosity change rate was calculated based on (Formula 1) and evaluated based on the following criteria. The results are summarized in Table 2.

Viscosity change rate = a / (a + b) (Formula 1)
[Criteria]
⊚: Viscosity change rate is less than 2% ○: Viscosity change rate is 2% or more and less than 5% Δ: Viscosity change rate is 5% or more and less than 10% ×: Viscosity change rate is 10% or more

<Discharge stability>
An inkjet printer (IPSiO GX5000, manufactured by Ricoh Co., Ltd.) is filled with each ink, and under an environment adjusted to a temperature of 24 ± 0.5 ° C. and a humidity of 50 ± 5% RH, 5% of the area of A4 size paper is solid. Print the chart to be filled with an image on gloss paper for printing (product name: LumiArtGloss with a basis weight of 90 g / m ² , manufactured by Enso, liquid absorption characteristics: transfer amount of pure water at a contact time of 100 ms, 2.3 mL / m ² ). However, the evaluation was made based on the following criteria based on the streaks and irregularities in the printed image. The results are summarized in [Table 2].

[Evaluation criteria]
○: No streaks or disturbances △: Slight streaks or disturbances ×: Significant streaks or disturbances

<Image density>
Ink printers (IPSiO GX5000, manufactured by Ricoh Co., Ltd.) are filled with each ink so that the amount of ink ejected becomes even in an environment adjusted to a temperature of 24 ± 0.5 ° C and a humidity of 50 ± 5% RH. By changing the drive voltage of the piezo element, a solid image of 10 points ■ can be printed on gloss paper (product name: LumiArtGloss with a basis weight of 90 g / m ² , manufactured by Enso, liquid absorption characteristics: pure water with a contact time of 100 ms. The transfer amount of 2.3 mL / m ² ) was printed. The image density of the printed image was measured using a reflective color spectrophotometric densitometer (manufactured by X-Rite). The results are summarized in [Table 2].

[Evaluation criteria]
⊚: 1.8 or more ○: 1.6 or more and less than 1.8 Δ: 1.4 or more and less than 1.6 ×: less than 1.4 The liquid absorption characteristics of the recording medium used in each of the above evaluations are It was determined by measuring the transfer amount of pure water using a dynamic scanning absorbent (K350 series D type, manufactured by Kyowa Seiko Co., Ltd.). The transfer amount at the contact time of 100 ms was obtained by interpolation from the measured value of the transfer amount at the contact time in the vicinity of the contact time.

From the above results, inks using a urethane resin having a polyester polyol having a bisphenol skeleton structure, particularly an emulsion containing a polyurethane resin having a structure represented by the above formula (1), have abrasion resistance, blocking resistance, and image density. It is clear that an excellent image can be formed, and that the ink is also excellent in storage stability and ejection stability.

Japanese Unexamined Patent Publication No. 2013-10816

Claims (12)

Includes a structure derived from a polyester polyol, a polyurethane resin having a structure derived from a short chain polyol having a hydrophilic group, have a structure in which the polyester polyol is represented by the following general formula (1), wherein the hydrophilic group The value of the ratio of the number of moles of the short-chain polyol having the above to the sum of the number of moles of the polyester polyol and the number of moles of the short-chain polyol is 0.17 or more and 0.35 or less is dispersed in the aqueous medium. Dispersion used as a binder for inkjet ink .

(However, R1 and R2 in the general formula (1) independently represent a hydrogen atom or an alkyl group.) The dispersion according to claim 1, wherein the polyester polyol contains a structure derived from an aromatic polycarboxylic acid. The dispersion according to claim 2, wherein the structure derived from the aromatic polycarboxylic acid has at least one of the structure represented by the following general formula (2) and the structure represented by the following general formula (3).

The dispersion according to any one of claims 1 to 3, wherein the glass transition temperature is 70 ° C. or higher. The dispersion according to any one of claims 1 to 4, wherein the polyurethane resin further has a structure derived from an alicyclic polyisocyanate. An ink comprising the dispersion according to any one of claims 1 to 5 . The ink according to claim 6 , which is used for printing on a coating recording medium. An ink containing container comprising an ink containing portion containing the ink according to claim 6 or 7 . An inkjet recording method in which the ink according to claim 6 is ejected from a nozzle of an ejection head, applied to a recording medium, and recorded. The inkjet recording method according to claim 9 , wherein the transfer amount of pure water to the recording medium at a contact time of 100 ms is 30 mL / m ² or less. An inkjet recording device having the ink container according to claim 8 and an ejection head for ejecting droplets of the ink. A recorded object having an image formed on a recording medium using the ink according to claim 6 or 7 .

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