JP2001002965A - Ink-jet recording ink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ink-jet recording ink improved in ink fixity and enabling excellent stability in jetting ink to be exhibited by including a polymeric compound having at least one specific amphoteric ion group in an ink-jet recording ink comprising at least a colorant and water. SOLUTION: This ink is prepared by including a polymeric compound having at least one of amphoteric ion groups of formulas I to II [wherein (n) is 2-8; (m) is 1-5; R1 and R2 are each an alkyl, an aralkyl or the like; (k) and (l) are each an integer of >=0 with proviso that (k) and (l) are 0 at the same time; and (k)+(l)+(m)<=8] in an ink-jet recording ink comprising at least a colorant and water. The above polymeric compound is obtained by preferably employing a radically polymerized material having at least one amino group capable of being quaternized or a resin composition comprising polyurethane, polyurea or the like each having at least one amino group capable of being quaternized as a raw material. Consequently, the ink is expected to be improved in ink fixity and stability in jetting ink.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink-jet recording ink used in an ink-jet recording apparatus such as an ink-jet printer, and more particularly to a method of improving the hydrophilic resin to be added to the ink-jet recording ink. When an image is formed by discharging the ink onto a recording medium such as paper from an ink discharge head of an ink jet recording apparatus, the ink jet recording ink is stably discharged from the ink discharge head. Things.

[0002]

2. Description of the Related Art Conventionally, as inks used in ink jet recording apparatuses such as ink jet printers, water-based inks have been widely used in addition to oil-based inks in terms of easy handling and safety.

[0003] Here, as the aqueous ink, a dye is used as a colorant, and the dye is dissolved in an aqueous medium, or a pigment such as carbon black is used as a colorant. Dispersions are commonly used.

Here, in such an aqueous ink, in order to improve the fixability of the ink to a recording medium and the dispersion stability of a pigment in an aqueous medium, a conventional ink is used.
It has been practiced to add a hydrophilic resin obtained by copolymerizing a resin such as polyurethane, polyurea, polyamide, or polyester with hydrophilic polyethylene glycol or the like.

However, when the above-mentioned hydrophilic resin is added to the ink for ink jet recording, the hydrophilic resin aggregates and clogs the ink discharge head, or the viscosity of the ink for ink jet recording increases, There have been problems such as poor ink dischargeability.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems in ink jet recording ink. This ink jet recording ink is supplied from an ink ejection head of an ink jet recording apparatus to a paper. In the case of forming an image by discharging onto a recording medium such as the one described above, it is necessary to improve the fixability and the like of the ink for ink jet recording and to stably discharge the ink for ink jet recording from the ink discharge head. Is the subject.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an ink jet recording ink according to the present invention is an ink jet recording ink having at least a coloring material and water. A polymer compound having at least one zwitterionic group represented by the formulas (1) to (3) is contained.

Here, if the number of n, m, k, and l in the above general formulas (1) to (3) is too small, the fixability of the ink for ink jet recording can be sufficiently improved. On the other hand, if these numbers are too large, the ink for inkjet recording tends to agglomerate. Therefore, as described above, n is an integer of 2 to 8, m is an integer of 1 to 5, k, l Is an integer of 0 or more (except when both k and l are 0), and k + 1 + m
The relationship of ≦ 8 is satisfied.

Then, like the ink jet recording ink of the present invention, the general formula (1)
When a polymer compound having at least one zwitterionic group represented by the formulas (3) to (3) is contained, the fixability of the ink for inkjet recording to a recording medium is improved by the polymer compound having an amphoteric ion group. Thus, the aggregation of the ink for ink jet recording is suppressed, and the ink for ink jet recording can be stably ejected from the ink ejection head.

In the ink for ink jet recording according to the present invention, in order to obtain a high molecular compound having an amphoteric group represented by the above-mentioned general formulas (1) to (3), a raw material for the high molecular compound is described in claim 2. A radical polymer having a quaternizable amino group as described above, and at least one resin composition selected from a polyurethane, a polyurea, a polyamide and a polyester having a quaternizable amino group as shown in claim 3. Can be used,
Further, as described in claim 4, the first having a zwitterionic group.
And the second radical polymer can be grafted. The quaternizable amino group is an amino group having no active hydrogen and not participating in polymerization and not directly bonded to a carbonyl group or a sulfonyl group. And quaternized by reacting with halogenated carboxylic acids and lactones described below.

In order to obtain a radical polymer having a quaternizable amino group according to claim 2, for example, a radical polymer having a quaternizable amino group as shown in the following chemical formulas 2 and 3 is obtained. One or more radical polymerizable monomers are dissolved in water or an organic solvent, and radical polymerization is carried out by a radical polymerization initiator.

[0012]

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[0013]

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One or more of the above-mentioned radical polymerizable monomers having a quaternizable amino group and one or more of the radical polymerizable monomers having no quaternizable amino group. May be copolymerized at an arbitrary ratio.

Here, one or more radical polymerizable monomers having a quaternizable amino group as described above and one or two radical polymerizable monomers having no quaternizable amino group are used. In copolymerizing the above with
The sequence of the repeating units of each monomer in the copolymer can be adjusted according to the purpose, thereby changing the physical properties of the ink, the resistance of the ink image, and the like.

When it is desired to obtain a copolymer having the averaged properties of the high molecular compound obtained from each of the above monomers, a random copolymer of each monomer is obtained, and When obtaining a copolymer having the respective properties of the high molecular compound to be obtained,
A block copolymer of each monomer is obtained.

For example, in the case of a copolymer of styrene having a relatively high hydrophobicity and glass transition temperature and a radical polymerizable monomer having a quaternizable amino group, a quaternizable random copolymer can be used. A copolymer having a higher hydrophobicity and a higher glass transition temperature than a polymer compound composed of only a radical polymerizable monomer having an amino group can be obtained. In the block copolymer, a hydrophobic portion of polystyrene and a quaternary The hydrophilic portion of the polymer of the radical polymerizable monomer having a functionalizable amino group is present separately from each other, so that physical properties such as a so-called surfactant are obtained, and the glass transition temperature is also separately observed. It is thought to be.

The radical polymerizable monomer having no quaternizable amino group to be copolymerized with the above-described radical polymerizable monomer having a quaternizable amino group includes, for example, acrylic acid, sodium acrylate , Methacrylic acid, sodium methacrylate, acrylamide, methacrylamide, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, N, N
-Diethylacrylamide, N, N-dimethylmethacrylamide, acryloylmorpholine, methacryloylmorpholine, methyl acrylate, methyl methacrylate, styrene, 4-vinylphenol, sodium 4-vinylphenylsulfonate, vinyl acetate, acrylonitrile, methacrylonitrile, Vinyl chloride, maleic anhydride, vinylbenzoic acid, N-butylmaleimide and the like can be used.

Further, after radical polymerizing a radical polymerizable monomer having an amino group which is inactive to quaternization, a part or a part of the amino group which is inactive to quaternization in the radical polymer is obtained. All of them can be changed to quaternizable amino groups, or silane-based or titanium-based compounds having quaternizable amino groups can be used for radical polymers having no quaternizable amino groups. By reacting a surface modifier or performing a plasma treatment using NH ₃ , etc.
A quaternizable amino group may be introduced into the radical polymer.

In order to obtain a polyurethane, polyurea, polyamide or polyester having a quaternizable amino group as defined in claim 3, the monomer for polycondensation includes
For example, diamines, diols and amino alcohols having a quaternizable amino group as shown in the following chemical formulas 4 and 5 are used, and as is generally known, in the case of polyurethane, diisocyanate is used. And diols, in the case of polyurea diisocyanates and diamines, in the case of polyamides dicarboxylic acids or dicarboxylic acid dihalides and diamines, in the case of polyesters dicarboxylic acids or dicarboxylic acid dihalides and diols Can be synthesized by reacting the same.

[0021]

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[0022]

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Further, two or more of the above-mentioned diamines having a quaternizable amino group, diols and amino alcohols may be used, or other diamines having no quaternizable amino group. , Diols and amino alcohols can be used in combination.

In order to further improve the water solubility of the above-mentioned polyurethanes, polyureas, polyamides and polyesters having a quaternizable amino group, it is preferable to copolymerize polyethylene glycol or polyethylene glycol diamine.

The diisocyanates include, for example, m-phenylene diisocyanate, p-phenylene diisocyanate, 2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate, naphthalene-1,4-diisocyanate, diphenylmethane-isocyanate.
4,4'-diisocyanate, 3,3'-dimethoxy-
4,4'-biphenyl diisocyanate, 3,3'-diphenylmethane-4,4'-diisocyanate, xylylene-1,4-diisocyanate, xylylene-1,3
-Diisocyanate, 4,4'-diphenylpropane diisocyanate, 4,4'-diphenylhexafluoropropane diisocyanate, trimethylene diisocyanate, hexamethylene diisocyanate, propylene
1,2-diisocyanate, butylene-1,2-diisocyanate, cyclohexylene-1,2-diisocyanate, cyclohexylene-1,4-diisocyanate,
Cyclohexylene-1,3-diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,
4-bis (isocyanatomethyl) cyclohexane,
1,3-bis (isocyanatomethyl) cyclohexane, isophorone diisocyanate, dimers of the above isocyanates (uretondione), and diisocyanates of adducts obtained by adding the above isocyanates to both ends of diols and diamines Can be used.

Examples of the dicarboxylic acid include succinic acid, maleic acid, malonic acid, adipic acid, isophthalic acid, terephthalic acid, 4,4'-biphenyldicarboxylic acid and the like. As the dihalide, halides of these dicarboxylic acids can be used, and further, a polyamide or polyester can be synthesized by reacting tetracarboxylic dianhydride with diamines or diols.

The tetracarboxylic dianhydride includes, for example, pyromellitic dianhydride, 1,2,4,5
-Naphthalenetetracarboxylic dianhydride, 3,3 ',
4,4′-diphenyltetracarboxylic dianhydride, bis (2,3-dicarboxyphenyl) ether dianhydride,
2,2 ′, 3,3′-benzophenonetetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride, cyclopentanetetracarboxylic dianhydride, cyclobutanetetra Carboxylic dianhydride, tetrahydrofurantetracarboxylic dianhydride, or the like can be used.

The diamines having no quaternizable amino group include, for example, m-phenylenediamine, p-phenylenediamine, 1,8-diaminonaphthalene, m-xylylenediamine, p-xylylenediamine Rangeamine, ethylenediamine, 1,3-propylenediamine, 1,4-diaminobutane, 1,6-diaminohexane, 4,4′-diaminodiphenylmethane, 4,4′-
Diaminodicyclohexylmethane, 1,3-diaminocyclohexane, isophoronediamine, piperazine, 3,
9-bis (3-aminopropyl) -2,4,8,10-
Tetraoxaspiro [5.5] undecane, bis (3-
Aminopropyl) ether, 1,4-bis (3-aminopropoxy) butane, 1,2-bis (3-aminopropoxy) ethane, bis [2- (3-aminopropoxy) ethyl] ether, polyethylene glycol diamine, etc. Can be used.

Examples of the diols having no quaternizable amino group include ethylene glycol, diethylene glycol, triethylene glycol, and the like.
Polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, tetramethylene diol, polytetramethylene diol,
1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, resorcinol, bisphenol A, 4,4′-
Biphenol, 1,3-dimethylolbenzene, 1,3
-Cyclohexanediol, 1,4-dimethylolcyclohexane, 2,2-dimethylolpropionic acid and the like can be used.

The amino alcohols having no quaternizable amino group include, for example, aminoethanol, 4-aminobutanol, 2-aminopropanol, 2-hydroxymethylaniline, m-aminophenol, -Methylaminobutanol, 2-piperidineethanol, 4-piperidineethanol and the like can be used.

In order to obtain a polymer compound having an amphoteric group, a radical polymer having a quaternizable amino group as described above, or a polyurethane, a polyurea, or a polyamide having a quaternizable amino group is used. The quaternizable amino group in the polyester is quaternized. In addition, it is also possible to quaternize the quaternizable amino group at the stage of the monomer.

Here, when the quaternizable amino group in the radical polymer, polyurethane, polyurea, polyamide, polyester and these monomers is quaternized, a halogenated carboxylic acid or lactone is used. To react.

When the quaternizable amino group is quaternized by reacting a halogenated carboxylic acid,
For example, when the reaction is carried out in the presence of a base in water or a mixed solvent of water and an organic solvent, and when the lactone is reacted to quaternize the quaternizable amino group, for example, an organic solvent is used. In the reaction.

As the above-mentioned halogenated carboxylic acid, for example, a halogenated carboxylic acid shown in the following chemical formula 6 is used. As the above-mentioned lactone, for example, a lactone shown in the following chemical formula 7 is used. Can be used.

[0035]

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[0036]

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Further, as shown in claim 4, the first radical polymer having a zwitterionic group and the second radical polymer are grafted to form the above-mentioned general formula (1)
In order to obtain a polymer compound having at least one zwitterionic group represented by (3) to (3), the following method can be used.

As a first method, the above-mentioned chemical formula 2 and chemical formula 3
Using a vinyl monomer having an amphoteric ionic group obtained by reacting a vinyl monomer having an amino group capable of quaternization shown in the above with the halogenated carboxylic acid or lactone shown in the above formula 6 or 7; As shown in FIG.
Compounds having a functional group Y having an active hydrogen such as H, -NH ₂ and a functional group functioning as a radical polymerization chain transfer agent such as -SH, for example, YR-SH (formulae) such as mercaptoethanol and mercaptoethylamine Wherein R is a divalent organic group.), The above-mentioned vinyl monomer having an amphoteric group is subjected to radical polymerization, and a terminal having a zwitterionic group to which a functional group Y having an active hydrogen is bonded at a terminal. 1
To obtain a radical polymer of

[0039]

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Then, as shown in the following chemical formula 9, the first radical polymer having an amphoteric ionic group having a functional group Y having an active hydrogen bonded to the terminal obtained as described above,
-COCl, -CO which reacts and binds with the above functional group Y
The first radical polymer having an amphoteric ionic group was grafted to the second radical polymer by reacting with a second radical polymer having a functional group X such as OPh, -NCO and an acid anhydride group. A high molecular compound is obtained. In the following chemical formula 9, Z is a bond newly formed by the reaction between the functional group X and the functional group Y. For example, -C
OO-, -NHCOO-, -NHCOONH-, -NH
COS-, -COS-, -CONH- and the like.

[0041]

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The second method is as follows:
As shown in a compound having a functional group which functions as a radical polymerization chain transfer agent -SH or the like and the functional group Y having the above -OH, an active hydrogen such as -NH ₂ Y-R-S
Using H, this compound is converted to -COCl, -COOPh,-
By reacting with a second radical polymer having a functional group X such as NCO or an acid anhydride group, the second radical polymer is reacted with-
A functional group functioning as a radical polymerization chain transfer agent such as SH is bonded.

[0043]

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Then, as shown in the following chemical formula 11, -S
The above-mentioned vinyl monomer having an amphoteric group is radically polymerized with respect to a second radical polymer to which a functional group functioning as a radical polymerization chain transfer agent such as H is bonded, and the first radical having an amphoteric ion group is first polymerized. Radical polymer is second
To obtain a polymer compound grafted on the radical polymer of the above.

[0045]

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Here, in the above first and second methods, the second radical polymer having the functional group X which reacts with and binds to the functional group Y having active hydrogen has the above functional group X. It can be obtained by polymerizing one or two or more vinyl monomers or a vinyl monomer having a functional group X and another vinyl monomer.

Examples of the vinyl monomer having the functional group X include acrylic acid, acrylic acid chloride, methacrylic acid, methacrylic acid chloride, phenyl acrylate, (4-nitrophenyl) methacrylate, Vinyl benzene sulfonic acid chloride, 4-vinylphenyl isocyanate, 4-vinylbenzyl isocyanate, methacryloyloxyethyl isocyanate, maleic anhydride, itaconic acid or 4- (methacryloylamino) phthalic anhydride can be used. To adjust the hydrophobicity, for example, methyl methacrylate, ethyl methacrylate, butyl methacrylate,
Methacrylates and acrylates such as hexyl methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate, hexyl acrylate, dodecyl acrylate; styrene, α-methylstyrene, vinyl biphenyl, vinyl naphthalene, 4- Hydrophobic monomers such as aromatic vinyl such as propyloxystyrene and 4-hexyloxystyrene; and vinyl ethers such as methyl vinyl ether, butyl vinyl ether and hexyl vinyl ether can be used.

Examples of the compound having a functional group Y having an active hydrogen such as —OH and —NH ₂ and a functional group functioning as a radical polymerization chain transfer agent such as —SH include the above-mentioned mercaptoethanol and mercaptoethylamine. other,
For example, mercapto compounds such as mercaptopropanol, mercaptophenol, mercaptopropylamine, mercaptobenzylamine, mercaptoacetic acid and mercaptopropionic acid, and functional groups having active hydrogen such as dithiocarbamates, triphenylmethylazobenzenes, and tetraphenylethanes And a chain transfer agent into which Y has been introduced.

In the first and second methods, the vinyl monomer having a quaternizable amino group shown in the above chemical formulas 2 and 3 and the halogenated carboxylic acid shown in the above chemical formula 6 or 7 are used. Although a vinyl monomer having a zwitterionic group reacted with an acid or a lactone was used,
After polymerizing the vinyl monomer having a quaternizable amino group shown in Chemical formula 2 and Chemical formula 3, the above Chemical formula 6 or Chemical formula 7
It is also possible to react with a halogenated carboxylic acid or lactone shown in the above to form zwitterion.

Further, in the ink for ink jet recording according to the present invention, in addition to the above-mentioned polymer compound having an amphoteric ionic group, an appropriate coloring material is added to an aqueous medium and the properties of the ink are improved. Therefore, for example, a water-soluble resin, a fungicide, a preservative, a pH adjuster, a chelating agent, an oxygen absorber, a rust inhibitor, a quencher, and the like can be added.

Here, as the aqueous medium, water alone or a mixed solvent of water and an aqueous organic solvent can be used.

The above-mentioned aqueous organic solvent includes
In order to enhance the drying property of the ink and speed up the fixing of the ink to the recording medium, for example, aliphatic alcohols having 1 to 5 carbon atoms such as methyl alcohol, ethyl alcohol, n-propyl alcohol, and isopropyl alcohol are preferably used. And an aliphatic alcohol having 1 to 3 carbon atoms.

In order to improve the moisturizing property of the ink and to adjust the viscosity and the like, monoalkylene glycols such as ethylene glycol, propylene glycol, butylene glycol and hexylene glycol, and dialkylenes such as diethylene glycol and dipropylene glycol are used. Glycols, trialkylene glycols such as triethylene glycol, and polyhydric alcohols such as glycerin, and urea, amides, cyclic amides,
Amphiphilic substances such as alkanolamines can also be added.

Further, inorganic salts such as lithium bromide, sodium bromide and sodium chloride having high hygroscopicity and solubility in water, sodium acetate, sodium toluenesulfonate, sodium phthalate, ammonium acetate and triethanolamine acetate And other organic salts can also be added.

As the coloring material to be added to the above-mentioned aqueous medium, known water-soluble dyes such as acidic dyes, direct dyes and reactive dyes, oil-soluble dyes and pigments which have been generally used can be used. Can be.

The above dyes include, for example,
C. I. Acid Yellow 17, 23, 42, 44, 7
9, 142; I. Acid Red 1,8,13,1
4,18,26,27,35,37,42,52,8
7, 89, 92, 97, 106, 111, 114, 11
5,186,249,254,289; I. Acid blue 9, 29, 45, 92, 249; I. Acid Black 1, 2, 7, 24, 26, 94; C.I. I.
Direct Yellow 1,12,24,26,33,4
4, 50, 86, 120, 142, 144; I. Direct red 1,4,9,13,17,20,28,
31, 39, 80, 81, 89, 225, 227;
I. Direct blue 1,2,6,15,22,25,
71, 76, 79, 86, 87, 98, 163, 16
5,199,202; C.I. I. Direct Black 1
9, 22, 32, 38, 51, 56, 71, 74, 7
5,77,168,171; C.I. I. Basic Yellow 1,2,11,13,14,15,19,21,2
3,24,28,29,32,36,40,41,4
5,49,53,63,64,65,67,70,7
3,77,87,91; C.I. I. Basic Red 2,
12, 13, 14, 15, 18, 22, 23, 24, 2
7, 35, 36, 38, 39, 46, 49, 51, 5
2, 68, 70, 73, 78, 82, 102, 104,
109, 112; I. Basic Blue 1,3
5,7,9,21,22,26,35,41,45,5
4,62,65,66,67,69,75,77,8
9, 92, 93, 105, 117, 120, 122, 1
24, 129, 137, 141, 155; I. Basic black 2, 8; I. Reactive yellow 1,5,11,13,14,20,21,22,25,
C. 40, 47, 51, 55, 65, 67; I. Reactive Red 1,14,17,25,26,32,3
7,44,46,55,66,74,79,96,9
7; I. Reactive Blue 1,2,7,14,1
5,23,32,35,38,41,63,80,9
5; I. Reactive Black 3,4,7,11,
12, 17 etc. can be used.

The above-mentioned pigments include azo, phthalocyanine, anthraquinone, quinacridone, dioxazine, indigo, thioindigo, perylene, aniline black, azomethine, rotamin B lake, carbon black, surface black Carbon black or the like having improved water dispersibility by modification can be used. I. Pigment Yellow 1, 2,
3,13,16,83,93,95,151,154
180; I. Pigment Red 5, 7, 12, 4
8, 57, 112, 122; I. Pigment Blue 1, 2, 3, 15: 3, 16 and the like are used.

Here, as to the amount of the coloring material to be added to the aqueous medium, if the amount is too small, a sufficient color is not given to the ink, while if the amount is too large, the coloring material is added. In general, the coloring material is added to the ink for inkjet recording in a range of 0.1 to 20% by weight because the dissolution and dispersion of the coloring material cannot be sufficiently performed.

Further, a water-soluble resin can be added for the purpose of improving the fixability of the ink for ink jet recording and the dispersibility of the pigment.

Examples of the water-soluble resin include cellulose derivatives such as hydroxyethylcellulose, carboxymethylcellulose, and viscose; natural polymers such as alginic acid, gum arabic, tragacanth, ligninsulfonic acid, and gelatin; and phosphoric acid. Starch derivatives such as starch and carboxymethyl starch salt, polyacrylic acid, polymethacrylic acid, polyvinyl sulfate, polyvinyl sulfonic acid, condensed naphthalene sulfonic acid, ethylene-acrylic acid copolymer, styrene-acrylic acid copolymer, styrene-methacrylic Acid copolymer, acrylic ester-acrylic acid copolymer, acrylic ester-methacrylic acid copolymer, styrene-maleic acid copolymer, styrene-
Maleic acid ester copolymer, styrene-itaconic acid copolymer, itaconic acid ester-itaconic acid copolymer, vinylnaphthalene-acrylic acid copolymer, vinylnaphthalene-methacrylic acid copolymer, vinylnaphthalene-itaconic acid copolymer Coalescence, phenolic resin, polyamide resin, polyimide resin, polyamic acid resin, epoxy resin, polyester resin, polyurethane resin, polyurethane-urea resin, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkylamine, polyoxyethylene sorbitan fatty acid ester, polyvinyl Alcohol, polyvinylpyrrolidone, polyalkylene cation,
Synthetic resins such as phthalated gelatin and polymers having zwitterionic groups can be used.

[0061]

EXAMPLES Hereinafter, the ink jet recording ink according to the embodiment of the present invention will be specifically described, and it will be apparent from comparative examples that the ink jet recording ink according to this embodiment has excellent ejection stability. To

Example 1 In this example, in obtaining a radical polymer having a quaternizable amino group, N, N-dimethylamino having a quaternizable amino group was used as the radical polymerizable monomer. Propyl acrylamide (produced by Kojin) was used.

The radical polymerizable monomer 7
Dissolve 8.1 g (0.5 mol) in 250 ml of dioxane, add 0.656 g (0.004 mol) of azobisisobutyronitrile as a radical polymerization initiator, and heat to 70 to 90 ° C. under a nitrogen atmosphere. The reaction product was stirred for 4 hours, and the resulting reaction product was treated with hexane 1
Purification was performed by reprecipitation twice using a mixed solvent of 800 ml and 200 ml of acetone.

Next, the reaction product was dried in a vacuum oven at 80 ° C. for 4 hours, and 62.4 g of poly (N, N-dimethylaminopropylacrylamide) consisting of a pale yellow solid having a quaternizable amino group was obtained. I got

Here, the poly (N, N-dimethylaminopropylacrylamide) composed of the light yellow solid was dissolved in water to prepare a 10% by weight aqueous solution of poly (N, N-dimethylaminopropylacrylamide). , BL
60 rpm using a BL-type viscometer with an adapter
The viscosity of this aqueous solution was measured under conditions of m and 25 ° C., and it was 6.5 cp.

In addition, the poly (N, N
-Dimethylaminopropylacrylamide) in 2N H
After the reaction with amino groups was completed by adding an excess of Cl solution, the remaining HCl was subjected to reverse titration using a 0.1 N NaOH solution. As a result, the content of quaternizable amino groups was 5.91 mmol / g.

Next, the poly (N,
N-dimethylaminopropylacrylamide) 8.46
g (0.05 mol of quaternizable amino groups) and 2.0 g (0.05 mol) of sodium hydroxide in distilled water 7
Then, while stirring these, 7.65 g (0.05 mol) of 3-bromopropanoic acid as a halogenated carboxylic acid was added thereto, and this was added to 40 to 5 g.
The mixture was heated to 0 ° C., stirred for 4 hours, and reacted as shown in the following Chemical Formula 12 to obtain an aqueous solution containing 20% by weight of a solid content mainly composed of a polymer compound having an amphoteric ionic group.

[0068]

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Then, 11.25 g of an aqueous solution containing 20% by weight of a solid content mainly containing the above-mentioned polymer compound having an amphoteric ionic group, and a carbon black having a carbon black concentration of 15.4% by weight. Aqueous dispersion (CAB-O
-JET 300: manufactured by CABOT).
Glycerin 5.3 g, isopropyl alcohol 2
g, 0.2 g of NaHCO ₃ , 0.3 g of proxel which is an antifungal agent, and 48.48 g of distilled water.
An ink jet recording ink of Example 1 was prepared.

Example 2 In this example, in preparing an ink for ink jet recording, the solid content mainly composed of the polymer compound having an amphoteric ionic group prepared in Example 1 was contained at 20% by weight. 25 g of an aqueous solution containing 20% by weight of the above-mentioned polymer compound having an amphoteric group was dispersed in an aqueous solution of carbon black having a carbon black concentration of 15.4% by weight by changing the amounts of the prepared aqueous solution and distilled water. 32.47 g of liquid and 5.3 of glycerin
g, 2 g of isopropyl alcohol, 0.2 g of NaHCO ₃ , 0.3 g of proxel, and 34.73 of distilled water.
g to prepare the ink for inkjet recording of Example 2.

(Examples 3 to 8) In these examples, in order to obtain a polymer compound having an amphoteric ionic group, the radical polymer having a quaternizable amino group was used as in Example 1 described above. While using poly (N, N-dimethylaminopropylacrylamide), the halogenated carboxylic acid to be reacted with this radical polymer was changed from that of Example 1 above, and in Example 3, 4-bromobutanoic acid was used. In Example 4, 6-bromohexanoic acid, in Example 5, 8-bromooctanoic acid, in Example 6, 2-bromopropanoic acid, in Example 7, 2-bromobutanoic acid, and in Example 8, Is 2-
Except that bromohexanoic acid was used, the other inks for ink jet recording of Examples 3 to 8 were prepared in the same manner as in Example 1 above.

(Comparative Examples 1 and 2) In these comparative examples, in order to obtain a polymer compound having an amphoteric ionic group, a radical polymer having an amino group capable of being quaternized was used as in Example 1 described above. While using poly (N, N-dimethylaminopropylacrylamide), the halogenated carboxylic acid to be reacted with this radical polymer was changed from that in Example 1 above, and in Comparative Example 1, 11-bromoundecanoic acid was used. In Comparative Example 2, 2-bromooctanoic acid was used.
In the same manner as in the case of the above, each inkjet recording ink of Comparative Examples 1 and 2 was prepared. In the polymer compound having an amphoteric group obtained in Comparative Example 1, n in the general formula (1) is 10, and the polymer compound having an amphoteric group obtained in Comparative Example 2 is In the general formula (2), m was 6.

Comparative Example 3 In this comparative example, poly (N, N-dimethylaminopropylacrylamide), which is a radical polymer having an amino group capable of being quaternized and obtained in Example 1 described above, was halogenated. The aqueous solution of poly (N, N-dimethylaminopropylacrylamide) was used without reacting with the activated carboxylic acid, and the other conditions were the same as in Example 1 above, except that the ink for inkjet recording of Comparative Example 3 was used. Was prepared.

Next, the above Examples 1 to 8 and Comparative Examples 1 to
Each of the ink jet recording inks of No. 3 was 0.65
After filtration under pressure with a μm membrane filter, each of these ink jet recording inks was commercially available ink jet printer (MJ-510C, manufactured by Epson Corporation).
After installing in the ink cartridge for the above and mounting on the above inkjet printer and performing continuous printing for 1 hour,
After turning off the power of the ink jet printer, continuous printing was performed again for 1 hour after 30 days, the lack of a printed image at the time of printing after 30 days was examined, and the ejection stability of each of these inks for ink jet recording from the nozzle was evaluated. .

Here, in the evaluation of the ejection stability of each ink for ink jet recording, the case where no defect was found in the printed image after 30 days, which was the same as the initial printed image, When the chipping is almost inconspicuous, o, the chipping occurs in the printed image after 30 days of printing, but when the chipping in the printed image recovers to such an extent that the chipping is almost inconspicuous by repeating the nozzle cleaning, the nozzle cleaning is repeated. Even when the image was not recovered due to lack of a printed image due to printing after 30 days, the result is shown in Table 1 below as x.

[0076]

[Table 1]

As is apparent from the results, the above-mentioned chemical formula 1
Each of the ink jet recording inks shown in Examples 1 to 8 containing a polymer compound having an amphoteric ionic group satisfying the condition shown in (1) is a polymer having an amphoteric ionic group not satisfying the condition shown in Chemical Formula (1) The inkjet recording inks of Comparative Examples 1 and 2 containing the compound and the polymer compounds of Comparative Example 3 containing the polymer compound in which the quaternizable amino group in the radical polymer was not quaternized and not amphoteric ionized were contained. The ejection stability was improved as compared with the ink jet recording ink.

Example 9 In this example, in order to obtain a radical polymer having a quaternizable amino group, the same N, N-dimethylaminopropylacrylamide as in Example 1 was used as the radical polymerizable monomer. (Manufactured by Kojinsha Co., Ltd.) and use this radical polymerizable monomer
g (0.5 mol) was dissolved in 250 ml of dioxane, and 0.656 g (0.004 mol) of azobisisobutyronitrile as a radical polymerization initiator and 1.954 g (0.000 g) of 2-mercaptoethanol as a chain transfer agent were dissolved therein. .
025 mol) in a nitrogen atmosphere.
The mixture was heated to ９０90 ° C. and stirred for 4 hours to react. The obtained reaction product was purified by reprecipitation twice using 2000 ml of hexane.

Then, the reaction product was dried in a vacuum oven at 80 ° C. for 4 hours, and 58.77 g of poly (N, N-dimethylaminopropylacrylamide) consisting of a pale yellow solid having a quaternizable amino group was obtained. I got

Here, poly (N, N-dimethylaminopropylacrylamide) composed of the pale yellow solid was dissolved in water to prepare a 10% by weight aqueous solution of poly (N, N-dimethylaminopropylacrylamide). BL
60 rpm using a BL-type viscometer with an adapter
The viscosity of this aqueous solution was measured under the conditions of m and 25 ° C. and found to be 2.5 cp.

Further, the poly (N, N
-Dimethylaminopropylacrylamide) in 2N H
After the reaction with amino groups was completed by adding an excess of Cl solution, the remaining HCl was subjected to reverse titration using a 0.1 N NaOH solution. As a result, the content of quaternizable amino groups was It was 5.984 mmol / g.

Next, the poly (N,
N-dimethylaminopropylacrylamide) 8.36
g (0.05 mol of quaternizable amino groups) and 2.0 g (0.05 mol) of sodium hydroxide in distilled water 7
Then, while stirring these, 7.65 g (0.05 mol) of 3-bromopropanoic acid as a halogenated carboxylic acid was added thereto, and this was added to 40 to 5 g.
The mixture was heated to 0 ° C., stirred for 4 hours, and reacted to obtain an aqueous solution containing a solid content of 20% by weight mainly containing a polymer compound having an amphoteric ion group.

The ink jet recording of Example 9 was carried out in the same manner as in Example 1 above, using an aqueous solution containing 20% by weight of a solid content mainly composed of the polymer compound having an amphoteric ionic group. An ink for use was prepared.

(Examples 10 to 19) In these examples, in order to obtain a polymer compound having an amphoteric ionic group, a radical polymer having a quaternizable amino group was used as in Example 9 described above. While using poly (N, N-dimethylaminopropylacrylamide), the halogenated carboxylic acid to be reacted with this radical polymer was changed from that in Example 9 above, and in Example 10, 0.05 mol of 4-bromobutanoic acid was used. In Example 11, 0.05 mol of 6-bromohexanoic acid, 0.05 mol of 8-bromooctanoic acid in Example 12, and 0.04 mol of 3-bromopropanoic acid in Example 13.
And 0.01 mol of 8-bromooctanoic acid in Example 1
In Example 4, 0.03 mol of 4-bromobutanoic acid and 6-
0.02 mol of bromohexanoic acid, 0.05 mol of 2-bromopropanoic acid in Example 15, 0.05 mol of 2-bromobutanoic acid in Example 16,
In Example 17, 2-bromohexanoic acid 0.05 m
ol, in Example 18, 0.025 mol of 2-bromopropanoic acid and 0.025 mol of 2-bromohexanoic acid
ol and 0.025 mol of 3-bromopropanoic acid and 0.025 m of 2-bromopropanoic acid in Example 19.
ol and the others are the same as those in Example 9 described above.
In the same manner as in the case of the above, each ink jet recording ink of Examples 10 to 19 was prepared.

Next, Examples 9 to 10 prepared as described above were used.
Regarding each of the 19 inkjet recording inks, in the same manner as in Examples 1 to 8 and Comparative Examples 1 to 3,
The ejection stability from the nozzle was evaluated, and the results are shown in Table 2 below.

[0086]

[Table 2]

As is apparent from the results, the above-mentioned chemical formula 1
Each of the ink jet recording inks of Examples 9 to 19 containing a high molecular compound having an amphoteric ionic group satisfying the conditions shown in (1) to (4) above has a more stable ejection than the ink jet recording inks of Comparative Examples 1 to 3. Had improved.

(Embodiment 20) In this embodiment, 4
In obtaining a radical polymer having a gradable amino group, the above-mentioned N, N-
Dimethylaminopropylacrylamide (produced by Kojin)
And N, N-dimethylacrylamide using N, N
-Dimethylaminopropylacrylamide 31.24
g (0.2 mol) and 29.74 g (0.3 mol) of N, N-dimethylacrylamide, except that the quaternizable amino group is the same as in Example 9 above. 51.5 g of a copolymer of N, N-dimethylaminopropyl methacrylamide and N, N-dimethylacrylamide consisting of a pale yellow solid was obtained as a radical polymer having the following formula:

Here, an excess of 2N HCl solution was added to the copolymer of N, N-dimethylaminopropylacrylamide and N, N-dimethylacrylamide obtained as described above to complete the reaction with the amino group. After that, the remaining HCl was subjected to reverse titration using a 0.1 N NaOH solution. As a result, the content of the quaternizable amino group was 3.0 mmol.
1 / g, and the molar composition ratio of N, N-dimethylaminopropylacrylamide and N, N-dimethylacrylamide in the above copolymer is 0.36: 0.64.
It turned out to be.

Then, 5.73 g (0.0172 mol of quaternizable amino group) of the copolymer of N, N-dimethylaminopropylacrylamide and N, N-dimethylacrylamide obtained as described above, and water 0.0172 mol of sodium oxide was dissolved in 72.43 g of distilled water, and while stirring these, 0.0172 mol of 4-bromobutanoic acid as a halogenated carboxylic acid was added thereto, and the mixture was heated to 40 to 50 ° C. The mixture was stirred and reacted for 4 hours to obtain an aqueous solution containing 20% by weight of a solid content mainly composed of a polymer compound having an amphoteric ion group.

The ink jet recording of Example 20 was carried out in the same manner as in Example 1 above, using an aqueous solution containing 20% by weight of solids mainly composed of the above-mentioned polymer compound having an amphoteric group. An ink for use was prepared.

(Examples 21 to 25) In these examples, in order to obtain a high molecular compound having an amphoteric ionic group, the radical polymer having an amino group capable of being quaternized was used in the same manner as in the above Example 20. While a copolymer of N, N-dimethylaminopropylacrylamide and N, N-dimethylacrylamide was used, the halogenated carboxylic acid to be reacted with this copolymer was changed from that of Example 20 to Example 21. In Example 22, 0.0172 mol of 2-bromopropanoic acid in Example 22, 0.0172 mol of 3-bromobutanoic acid in Example 23, and 0.0172 mol of 3-bromobutanoic acid in Example 24. Acid 0.0086mo
1 and 0.0086 mol of 2-bromopropanoic acid, and in Example 25, 0.0086 mol of 2-bromopropanoic acid.
mol and 0.0086 mol of 8-bromooctanoic acid were used, and the other conditions were the same as in Example 20 to prepare the inks for inkjet recording of Examples 21 to 25.

Next, Example 20 prepared as described above was prepared.
For each of the ink jet recording inks Nos. 1 to 25, the ejection stability from the nozzle was evaluated in the same manner as in Examples 1 to 8 and Comparative Examples 1 to 3, and the results are shown in Table 3 below. Was.

[0094]

[Table 3]

As is apparent from the results, the above-mentioned chemical formula 1
Each of the ink jet recording inks of Examples 20 to 25 containing a high molecular compound having an amphoteric ionic group satisfying the conditions shown in Tables 1 and 2 was also more stable in ejection than the ink jet recording inks of Comparative Examples 1 to 3. Had improved.

(Embodiment 26) In this embodiment, 4
In obtaining a radical polymer having a gradable amino group, the above-mentioned N, N-
Dimethylaminopropyl methacrylamide (Kojinsha)
And methoxypolyethylene glycol monomethacrylate (manufactured by NOF Corporation: PME-200).
17.0 dimethylaminopropyl methacrylamide
3 g (0.1 mol), 110.4 g (0.4 mol) of methoxypolyethylene glycol monomethacrylate
Otherwise, in the same manner as in Example 1 above, N, N-dimethylaminopropyl methacrylamide composed of a viscous liquid and a methoxypolyethylene as a radical polymer having a quaternizable amino group are used. 90 g of a copolymer with glycol monomethacrylate was obtained.

Here, an excess of 2N HCl solution was added to the copolymer of N, N-dimethylaminopropyl methacrylamide and methoxypolyethylene glycol monomethacrylate obtained as described above to complete the reaction with the amino group. After that, the remaining HCl was subjected to reverse titration using a 0.1 N NaOH solution. As a result, the content of the quaternizable amino group was 0.56621 mmol / g, and the above copolymer The molar composition ratio of N, N-dimethylaminopropyl methacrylamide and methoxypolyethylene glycol monomethacrylate is 0.147: 0.85
It turned out to be 3.

Then, the copolymer 1 of N, N-dimethylaminopropyl methacrylamide and methoxypolyethylene glycol monomethacrylate obtained as described above was prepared.
7.66 g (0.010 mol of quaternizable amino groups)
And 0.01 mol of sodium hydroxide.
43 g, and while stirring these, 4-bromobutanoic acid as a halogenated carboxylic acid was added to the solution.
1 mol was added, and the mixture was heated to 40 to 50 ° C. and stirred for 4 hours to react, thereby obtaining an aqueous solution containing 20% by weight of a solid content mainly composed of a polymer compound having an amphoteric ion group.

The ink jet recording of Example 26 was carried out in the same manner as in Example 1 above, using an aqueous solution containing 20% by weight of a solid content mainly composed of the polymer compound having an amphoteric ionic group. An ink for use was prepared.

(Examples 27 to 31) In these examples, in order to obtain a polymer compound having an amphoteric ionic group, a radical polymer having an amino group capable of being quaternized was used in the same manner as in Example 26 described above. While using a copolymer of N, N-dimethylaminopropyl methacrylamide and methoxypolyethylene glycol monomethacrylate,
The halogenated carboxylic acid to be reacted with this copolymer was changed from that of Example 26 described above, and
0.01 mol of bromohexanoic acid, 0.01 mol of 2-bromopropanoic acid in Example 28, 0.01 mol of 2-bromobutanoic acid in Example 29,
In Example 30, 3-bromopropanoic acid 0.005
mol and 0.005 mol of 2-bromopropanoic acid,
In Example 31, 2-bromopropanoic acid 0.005
mol and 0.005 mol of 8-bromooctanoic acid, and otherwise, the inks for inkjet recording of Examples 27 to 31 were prepared in the same manner as in Example 26 above.

Then, Example 26 prepared as described above was prepared.
For each of the ink jet recording inks Nos. 1 to 31, the ejection stability from the nozzle was evaluated in the same manner as in Examples 1 to 8 and Comparative Examples 1 to 3 above, and the results are shown in Table 4 below. Was.

[0102]

[Table 4]

As is apparent from the results, the above-mentioned chemical formula 1
Each of the ink jet recording inks of Examples 26 to 31 containing the polymer compound having an amphoteric ion group satisfying the conditions shown in (1) and (2) was more stable in ejection than the ink jet recording inks of Comparative Examples 1 to 3. Had improved.

(Embodiment 32) In this embodiment, 4
To obtain a resin composition having a gradable amino group, polyethylene glycol diamine having 2.00 g (0.01 mol) of 1,4-bis (3-aminopropyl) piperazine as a diamine component and a weight average molecular weight Mw of 1000 (Manufactured by Koei Chemical Industry Co., Ltd .: PEGPA-1000)
20 g (0.02 mol) and 6.54 g (0.02 g) of isophorone diisocyanate as a diisocyanate component.
294 mol), and these were added to 66.6 g of dimethylformamide (hereinafter abbreviated as DMF).
The mixture was heated to 0 to 60 ° C. and stirred for 7 hours to react. The obtained reaction product was purified by reprecipitation twice using 1800 ml of acetone.

Then, the reaction product was heated at 85 ° C. for 2.5 hours.
After vacuum drying for 1 hour, 13.3 g of polyurea which became a rubbery solid having a quaternizable amino group was obtained.

Next, 2.0 g of the polyurea obtained as described above (0.0140 mol of quaternizable amino groups)
Was added to 21.16 g of distilled water, and 2.14 g of 3-bromopropanoic acid was added thereto as a halogenated carboxylic acid.
(0.0140 mol), 0.01% sodium hydroxide
40 mol was added, and the mixture was heated to 40 to 50 ° C. and stirred for 4 hours to cause a reaction to obtain an aqueous solution containing 20% by weight of a solid content mainly composed of a polymer compound having an amphoteric ionic group.

The ink jet recording of Example 32 was carried out in the same manner as in Example 1 above, using an aqueous solution containing 20% by weight of a solid content mainly composed of the polymer compound having an amphoteric ionic group. An ink for use was prepared.

(Examples 33 to 37) In these examples, in order to obtain a polymer compound having an amphoteric ionic group, a resin composition having an amino group capable of being quaternized was used in the same manner as in Example 32 described above. While using a polyurea having a quaternizable amino group, the halogenated carboxylic acid to be reacted with this polyurea was changed from that in Example 32 described above, and in Example 33, 4-bromobutanoic acid was added.
014 mol, 0.014 mol of 6-bromohexanoic acid in Example 34 and 2-
0.014 mol of bromopropanoic acid, 0.014 mol of 2-bromobutanoic acid in Example 36, and 0.007 mol of 3-bromopropanoic acid in Example 37
And 0.007 mol of 2-bromopropanoic acid,
Otherwise, in the same manner as in Example 32 described above, ink-jet recording inks of Examples 33 to 37 were prepared.

(Comparative Examples 4 and 5) In these comparative examples, when a polymer compound having an amphoteric ionic group was obtained, a resin composition having a quaternizable amino group was used.
While the same polyurea having a quaternizable amino group as in Example 32 was used, the halogenated carboxylic acid to be reacted with this polyurea was changed from that in Example 32, and in Comparative Example 4, 11-bromo was used. Undecanoic acid,
In Comparative Example 5, 2-bromooctanoic acid was used, and in the other respects, ink jet recording inks of Comparative Examples 4 and 5 were prepared in the same manner as in Example 32 described above. In the polymer compound having an amphoteric ion group obtained in Comparative Example 4, n in the general formula (1) was 10, and the polymer compound having an amphoteric ion group obtained in Comparative Example 5 was In the general formula (2), m was 6.

Next, Example 32 prepared as described above was used.
-37 and each of the ink jet recording inks of Comparative Examples 4 and 5 was evaluated for the ejection stability from the nozzle in the same manner as in Examples 1 to 8 and Comparative Examples 1 to 3 above.
The results are shown in Table 5 below.

[0111]

[Table 5]

As is apparent from the results, the above-mentioned chemical formula 1
Each of the inks for ink jet recording shown in Examples 32 to 38 containing a high molecular compound having an amphoteric ionic group satisfying the condition shown in the following is a polymer having an amphoteric ionic group not satisfying the condition shown in the above chemical formula 1. The ejection stability was improved as compared with the ink jet recording inks of Comparative Examples 4 and 5 containing the compound.

(Embodiment 38) In this embodiment, 4
In obtaining a resin composition having a gradable amino group, the weight average molecular weight Mw is 100 as a diamine component.
40 g (0.04 mo) of polyethylene glycol diamine (manufactured by Koei Chemical Industry Co., Ltd .: PEGPA-1000).
l), 5.8 g of methyliminobispropylamine
(0.04 mol), 17.42 g (0.0784 g) of isophorone diisocyanate as a diisocyanate component.
mol), added to 108 g of DMF, heated to 50-60 ° C., stirred for 4 hours and reacted, and the resulting reaction product was purified by reprecipitation twice using 1800 ml of acetone. .

The reaction product was dried under vacuum at 80 ° C. for 4 hours to obtain 47.9 g of polyurea which became a rubbery solid having a quaternizable amino group.

Next, 3.77 g of the polyurea obtained as described above (0.024 mol of quaternizable amino groups)
Was added to 21.16 g of distilled water, and to this was added 3-bromopropanoic acid as a halogenated carboxylic acid in an amount of 0.024 m 2.
ol and 0.024 mol of sodium hydroxide, and the mixture was heated to 40 to 50 ° C. and stirred for 4 hours to cause a reaction, thereby obtaining an aqueous solution containing 20% by weight of a polymer compound having an amphoteric ion group.

Then, in the same manner as in Example 1 above, an ink jet recording ink of Example 38 was prepared using an aqueous solution containing 20% by weight of the polymer compound having an amphoteric ionic group.

(Examples 39 to 41) In these Examples, in order to obtain a polymer compound having an amphoteric ionic group, the same resin composition as in Example 38 was used as a resin composition having a quaternizable amino group. While using a polyurea having a quaternizable amino group, the halogenated carboxylic acid to be reacted with this polyurea was changed from that in Example 38 described above, and Example 39 was changed to 0.1-bromobutanoic acid.
024 mol, 0.040 mol of 6-bromohexanoic acid in Example 40 and 2-24 mol in Example 41.
Using 0.024 mol of bromopropanoic acid, the other conditions were the same as in Example 38 above, to prepare inks for inkjet recording of Examples 39 to 41.

Next, Example 38 prepared as described above was used.
For each of the ink jet recording inks Nos. 1 to 41, the ejection stability from the nozzle was evaluated in the same manner as in Examples 1 to 8 and Comparative Examples 1 to 3 above, and the results are shown in Table 6 below. Was.

[0119]

[Table 6]

As is clear from the results, the above-mentioned chemical formula 1
Each of the inks for ink jet recording shown in Examples 38 to 41 containing a polymer compound having an amphoteric ionic group satisfying the condition shown in (1) is a polymer having an amphoteric ionic group not satisfying the condition shown in the above chemical formula (1). The ejection stability was improved as compared with the ink jet recording inks of Comparative Examples 4 and 5 containing the compound.

Embodiment 42 In this embodiment, 4
In obtaining a radical polymer having a quaternizable amino group, N, N-dimethylaminopropylacrylamide having a quaternizable amino group as in Example 1 is used as the radical polymerizable monomer. , Poly (N,
N-dimethylaminopropylacrylamide) was obtained.

Then, the poly (N,
In quaternizing the quaternizable amino group in N-dimethylaminopropylacrylamide), β-propiolactone is used as a lactone, and the β-propiolactone and the poly (N, N-dimethylamino) are used. Propylacrylamide) in an organic solvent to give an aqueous solution containing a polymer compound having an amphoteric ion group in an amount of 20% by weight as shown in the following chemical formula (13).

[0123]

Embedded image

An ink jet recording ink of Example 42 was prepared in the same manner as in Example 1 above, using an aqueous solution containing 20% by weight of the polymer compound having an amphoteric ionic group.

(Examples 43 to 46) In these examples, in order to obtain a polymer compound having an amphoteric ionic group, the radical polymer having an amino group capable of being quaternized was used in the same manner as in the above Example 42. While poly (N, N-dimethylaminopropylacrylamide) having a quaternizable amino group is used, the lactone to be reacted with the poly (N, N-dimethylaminopropylacrylamide) is the same as that in Example 42 described above. In a modification, α-methyl-γ-butyrolactone was used in Example 43, β-butyrolactone was used in Example 44, γ-caprolactone was used in Example 45, and δ-octanolactone was used in Example 46. Otherwise, in the same manner as in Example 42 above, each of the ink jet recording inks of Examples 43 to 46 was used. Was prepared.

Next, Example 42 prepared as described above was prepared.
For each of the ink-jet recording inks Nos. 1 to 46, the ejection stability from the nozzles was evaluated in the same manner as in Examples 1 to 8 and Comparative Examples 1 to 3, and the results are shown in Table 7 below. Was.

[0127]

[Table 7]

As is clear from the results, the above-mentioned chemical formula 1
In each of the ink jet recording inks shown in Examples 42 to 46 in which the high molecular compound having an amphoteric ionic group satisfying the condition shown in the following is contained, the high-molecular weight compound having the amphoteric ionic group not satisfying the above-mentioned chemical formula 1 is also used. The ejection stability was improved as compared with the ink jet recording inks of Comparative Examples 1 and 2 containing the molecular compound.

Example 47 In this example, first, 151.4 g (0.969 mo) of N, N-dimethylaminopropylacrylamide (manufactured by Kojin Co., Ltd .: DMAPAA) was used.
l) was dissolved in 200 ml of acetone, and this was dissolved in an ice bath.
At a temperature of 0 to 10 ° C. while stirring.
-69.83 g of propiolactone (manufactured by Wako Pure Chemical Industries, Ltd.)
(0.969 mol) in 80 ml of acetone was added dropwise over 1 hour.

Then, when this was left at about 10 ° C. for 24 hours, a white precipitate was formed. This precipitate was collected by filtration, washed with acetone, dried in vacuo at 60 ° C. for 4 hours, and the zwitterionic group was removed. 202 g of a contained white vinyl monomer was obtained.

Further, styrene and maleic anhydride were used in a ratio of 1:
10 g of a styrene-maleic anhydride copolymer (SMA1000P, manufactured by Yoshimitsu Fujii Trading Co.) copolymerized at a molar ratio of 1
(Anhydride group 0.0495 mol) in acetone 500m
and 2-mercaptoethylamine.
After adding 30 ml of an aqueous solution of 72 g (0.1 mol) and reacting at room temperature for 48 hours, the solution was poured into dilute hydrochloric acid to neutralize it, and a white precipitate was obtained. The precipitate was collected by filtration and washed with water. Thereafter, the precipitate is dissolved in acetone and precipitated again with water. The precipitate is collected by filtration and dried in vacuo at 65 ° C. for 4 hours to obtain a radical polymer having a mercapto group.
44 g were obtained. In addition, in the radical polymer having a mercapto group, the ratio of the introduced mercapto group was determined by neutralization titration with a 0.1 N NaOH solution to be 3.
It was found to be 37 mmol / g.

Then, to 194.02 g of distilled water, 2.849 g (0.0096 mol of mercapto group) and 0.384 g (0.0096 mol) of sodium hydroxide were added to the above radical polymer having a mercapto group. 45. A vinyl monomer containing a zwitterionic group of 45.
656 g (0.20 mol) was added and dissolved, and heated to 78 ° C. in a nitrogen stream, and VA-044 (manufactured by Wako Pure Chemical Industries), which is an azo-based radical polymerization initiator, was stirred with stirring.
0.0004 mol, and while stirring this,
The mixture was heated at a temperature of 83 ° C. for 4 hours to obtain a colorless and transparent viscous aqueous solution containing 20% by weight of a polymer compound having an amphoteric ionic group.

In a 100 ml container, 12.5 g of an aqueous solution containing 20% by weight of the above-mentioned polymer compound having an amphoteric ionic group was added to carbon black (Deguss).
aAG: Printex70), 2.5 g of distilled water, 35 g of distilled water, and 2 glass beads having a diameter of 2 mm.
5 g was put therein, sealed, and shaken for 1 hour using a paint conditioner to obtain a pigment dispersion aqueous solution.

Next, this pigment dispersion aqueous solution was added to 60.0%
g, 5.3 g of glycerin, 2.0 g of isopropyl alcohol, 0.2 g of NaHCO ₃ , 0.3 g of proxel as a fungicide, and 32.2 g of distilled water in a mixture of Example 47. An ink for inkjet recording was prepared.

(Example 48) In this example, 352 ml of distilled water and N, N-dimethylacrylamide 9
1.9 g (0.927 mol) and potassium persulfate 7.
5 g (28 mmol) and 4-hydroxy-2,2,2
6,6-tetramethylpiperidine-1-oxyl 5.6
g (33 mmol) was placed in a reaction vessel, and while these were being stirred, the inside of the reaction vessel was depressurized and replaced with dry argon, and this operation was repeated five times to remove dissolved oxygen in the aqueous solution.

Then, the above aqueous solution was heated to 65 ° C.
2.9 g of sodium bisulfite (28 mmo)
l), and the mixture was stirred at this temperature for 10 hours to give poly (N, N-dimethylacrylamide) having 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl introduced into the terminal of the polymer. )) Was obtained.

Next, 230 g of the aqueous solution of poly (N, N-dimethylacrylamide) was placed in another reaction vessel.
And 75.35 g (0.33 g) of the same zwitterionic vinyl monomer used in Example 47 above.
mol) and 302 ml of distilled water were added and mixed, and reacted at 65 ° C. for 10 hours under an argon atmosphere to obtain an aqueous solution containing 20% by weight of a polymer compound composed of a block copolymer having an amphoteric ionic group. Was.

Using the aqueous solution containing 20% by weight of the polymer compound having an amphoteric group obtained as described above, Example 4 was carried out in the same manner as in Example 1 above.
Ink jet recording inks No. 8 were prepared.

(Example 49) In this example, an aqueous solution containing 20% by weight of a polymer compound composed of a block copolymer having an amphoteric ion group obtained in the same manner as in Example 48 above was used. In the same manner as in Example 2 above, an ink jet recording ink of Example 49 was prepared.

Comparative Example 6 In this comparative example, a commercially available pigment dispersant (Johnson polymer) was used instead of the aqueous solution containing 20% by weight of the high molecular compound having an amphoteric group used in Example 47 described above. Made by Joncry
163), and otherwise in the same manner as in Example 47, an aqueous pigment dispersion solution was obtained.

Then, this pigment dispersion aqueous solution was added to 60.0%
g, 5.3 g of glycerin, 2.0 g of isopropyl alcohol, 0.2 g of NaHCO ₃ , 0.3 g of proxel as a fungicide, and 32.2 g of distilled water in a ratio of Comparative Example 6. An ink for inkjet recording was prepared.

Next, the inks for ink jet recording of Examples 47 to 49 and Comparative Example 6 prepared as described above were also prepared in the same manner as in Examples 1 to 8 and Comparative Examples 1 to 3. Evaluate the discharge stability from the nozzle,
The results are shown in Table 8 below.

[0143]

[Table 8]

As is clear from the results, the above-mentioned chemical formula 1
Each of the ink jet recording inks of Examples 47 to 49 containing a zwitterionic group-containing polymer compound that satisfies the conditions shown in (1), (2), (3) is a commercially available pigment dispersant instead of such amphoteric group-containing polymer compound. The ejection stability was improved as compared with the ink jet recording ink of Comparative Example 4 used.

[0145]

As described above in detail, in the ink for ink jet recording according to the present invention, the inks for ink jet recording having at least a coloring material and water are added to the general formulas (1) to (3) )), A polymer compound having at least one zwitterionic group is contained, so that the polymer compound having the amphoteric ion group improves the fixability of the inkjet recording ink to a recording medium, and Agglomeration of the ink jet recording ink was suppressed, and the ink jet recording ink could be stably ejected from the ink ejection head.

Claims (4)

[Claims] 1. An ink jet recording ink having at least a coloring material and water, wherein a polymer compound having at least one kind of zwitterionic groups represented by the following general formulas (1) to (3): An ink for inkjet recording characterized by being contained. Embedded image In the above general formulas (1) to (3), n is an integer of 2 to 8, m is an integer of 1 to 5, R ₁ , R ₂
Is an alkyl group, an aralkyl group, or a group in which a substituent is bonded thereto, and R ₁ and R ₂ may be the same or different from each other, or may be bonded to each other to form a ring structure. Further, k and l are integers equal to or greater than 0 (except when both k and l are 0) and satisfy the relationship of k + 1 + m ≦ 8. 2. The ink for inkjet recording according to claim 1, wherein a radical polymer having a quaternizable amino group is used as a raw material of the polymer compound having an amphoteric ion group. Ink for inkjet recording. 3. The ink for inkjet recording according to claim 1, wherein the raw material of the polymer compound having an amphoteric ionic group is selected from polyurethane, polyurea, polyamide and polyester having a quaternizable amino group. Characterized by using at least one resin composition. 4. The ink jet recording ink according to claim 1, wherein the polymer compound having an amphoteric group is obtained by grafting a first radical polymer having an amphoteric group to a second radical polymer. An ink for inkjet recording, characterized in that it is made.