JP2005272848A - Ink-jet recording ink, recording method, print, and ink-jet recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink-jet recording ink having excellent dispersion stability and ejection stability, capable of providing high-grade images free from bleeding against plain paper and reclaimed paper, having high printing density and excellent in color development property, to provide a recording method using the ink, to provide prints, and to provide an ink-jet recording apparatus. <P>SOLUTION: The ink-jet recording ink comprises a colorant obtained by covering a pigment and/or a dye by a phase transition emulsification method, water, at least one compound selected from the group consisting of acetylene glycol surfactants and acetylene alcohol surfactants and a compound of 1,2-(4-10C alkyl)diol (or, also comprises a compound of a glycol ether) and is formed to have 25-45 mN/m surface tension. A recording method using the ink, prints and an ink-jet recording apparatus are also provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

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

Inkjet recording is a method of recording characters and figures on the surface of a recording medium by ejecting ink as small droplets from fine nozzles. As an ink jet recording method, an electrostrictive element is used to convert an electrical signal into a mechanical signal, and ink stored in the nozzle head is intermittently ejected to record characters and symbols on the surface of the recording medium. A method of recording characters and symbols on the surface of the recording medium, etc. by rapidly heating a part of the ink that is stored in the vicinity of the ejection part to generate bubbles and intermittently ejecting the volume due to the bubbles. It has been put into practical use.
Various characteristics are required for the ink used for such ink jet recording. For example, when printing on paper, which is the recording medium, there is no bleeding, good drying, uniform printing on the surface of various recording media, and adjacent colors in multicolor printing such as color printing Is required to not mix.

Ink jet recording inks are generally used in which various water-soluble dyes are dissolved in an aqueous medium. Recently, an ink in which a pigment is dispersed in an aqueous medium is also provided. This is because an ink using a pigment has characteristics of being superior in water resistance and light resistance as compared with an ink using a water-soluble dye. is there.
Many of the conventional inks using pigments mainly suppress penetration, thereby suppressing ink wetting on the paper surface, thereby keeping ink droplets near the paper surface and ensuring print quality. However, this type of ink has a problem of low adaptability to all types of paper. Specifically, the difference in bleeding due to the difference in the paper type is large, especially in recycled paper produced by mixing a large number of unspecified types of paper, the difference in ink wetting characteristics with respect to the used paper type There was a problem that the print quality was not stable due to the occurrence. In addition, the above-described ink takes time to dry the printed portion due to the characteristics of the ink, and particularly in multi-color printing such as color printing, adjacent colors are mixed. Furthermore, since the pigment remains on the surface of paper or the like, there is a problem that the scratching property is deteriorated.

  In order to solve such problems, attempts have been made to add penetrants in order to improve the permeability of ink into paper. For example, an example using glycol ether is disclosed, and an example using triethylene glycol monomethyl ether is disclosed in Patent Document 1: Japanese Patent Laid-Open No. 56-147861, and Patent Document 2: Japanese Patent Laid-Open No. 9-111165. Include examples using ethers of ethylene glycol, diethylene glycol or triethylene glycol. Patent Document 3: Addition of diethylene glycol monobutyl ether to US Pat. No. 5,156,675, and Patent Document 4: US Pat. No. 5,183,502 include Surfynol 465 (manufactured by Nisshin Chemical), which is an acetylene glycol surfactant. Patent Document 5: US Pat. No. 5,196,056 proposes the combined use of diethylene glycol monobutyl ether and Surfynol 465. Further, Patent Document 6: US Pat. No. 2,083,372 proposes to use ethers of diethylene glycol for the ink.

In addition, in conventional inks using pigments, it is generally performed to disperse pigments in an aqueous medium using a dispersant such as a surfactant or a polymer dispersant. There is a problem that it is not easy to improve the ink permeability while securing the ink.
In addition, in an ink having improved permeability by using a pigment dispersion in which a pigment is dispersed using a dispersant such as a surfactant or a polymer dispersant, the dispersant is simply adsorbed on the pigment surface. For this reason, when a strong shearing force is applied when ink is ejected through a thin nozzle, the adsorbing dispersant may be detached, dispersibility may be deteriorated, and ejection may become unstable. In addition, when the ink is stored for a long period of time, the dispersibility tends to become unstable. As a countermeasure, a method of increasing the amount of the dispersant added can be considered. In this case, since the amount of the dispersant dissolved in the ink without being adsorbed on the pigment surface increases, When printing is performed on recycled paper, bleeding is likely to occur, and the nozzles are likely to become unstable due to ink getting wet around the nozzle. Furthermore, when printing on plain paper or recycled paper with ink having improved permeability using a pigment dispersion in which a pigment is dispersed using a dispersant such as a surfactant or a polymer dispersant, a coloring component Tends to remain on the surface of the paper fiber on the surface of the recording medium, and there is a tendency that the printing density cannot be obtained and the coloring is not good. In general, since the viscosity of the ink tends to increase due to the dispersant that has not been adsorbed on the pigment surface from the beginning and is dissolved in the liquid or that has been detached from the pigment, the pigment content is limited. In many cases, particularly with plain paper and recycled paper, a sufficient print density cannot be obtained, so that good color development cannot be obtained and it is difficult to obtain high-quality print image quality. In addition, when the ink was stored for a long time in the state where the head was filled, the dispersion stability deteriorated, and it was found that the ink was difficult to be ejected from the nozzles of the printer.

On the other hand, for the purpose of improving ejection stability, dispersion stability, printing density, color developability, etc., an ink using a pigment whose surface has been subjected to some treatment has been proposed.
Examples of the ink using the treated pigment include those obtained by oxidizing the surface of pigment particles described in Patent Document 7: JP-A-8-319444, Patent Document 8: Japanese Patent Publication No. 7-94634. Patent Document 9: Encapsulated pigment fine particles described in JP-A-8-59715, Patent Document 10: JP-A-5-339516, Patent Document 11: JP-A-8-302227, Patent Document 12: JP-A-8-302228 and Patent Document 13: JP-A-8-81647 have been proposed in which a polymer is graft-polymerized on the surface of pigment particles.

  In addition to the above proposal, Patent Document 14: Japanese Patent Application Laid-Open No. 8-21815, Patent Document 15: Japanese Patent Application Laid-Open No. 8-295958, Patent Document 16: Japanese Patent Application Laid-Open No. 9-3376, and Patent Document 17: Japanese Patent Application Laid-Open No. Hei 8 JP-A No. 183920, Patent Document 18: JP-A-10-46075, Patent Document 19: JP-A-10-292143, Patent Document 20: JP-A-11-80633, Patent Document 21: JP-A-11-349870. Patent Publication 22: JP 2000-7961 A discloses an ink using a pigment coated with a resin having a film-forming property at room temperature by a phase inversion emulsification method, Patent Publication 23: JP 9-31360 A, Patent Document 24: Japanese Patent Application Laid-Open No. 9-217019, Patent Document 25: Japanese Patent Application Laid-Open No. 9-316353, Patent Document 26: Japanese Patent Application Laid-Open No. 9-104834 Patent Document 27: JP-A-9-151342, Patent Document 28: JP-A-10-140065, Patent Document 29: JP-A-11-152424, Patent Document 30: JP-A-11-166145, Patent Document 31: JP-A-11-166145, Patent Document 32: JP-A-11-199978, Patent Document 33: JP-A-11-209672 was coated with an anionic group-containing organic polymer compound by an acid precipitation method. Inks using pigments have been proposed.

However, an ink using a colorant obtained by a phase inversion emulsification method or an acid precipitation method and a surfactant such as the above-mentioned glycol ethers or acetylene glycol surfactant as a penetrant is a resin that is not adsorbed by the pigment. Is a coloring component when printed on plain paper or recycled paper due to the fact that the resin adsorbed by the pigment is detached and the amount of resin dissolved in the ink increases. Since the pigment is unlikely to remain on the paper fiber surface of the recording medium surface, it is difficult to obtain the printing density, the color is not good, the bleeding is likely to occur, the discharge around the nozzle is likely to become unstable due to the ink getting wet, etc. In particular, the image quality on plain paper and recycled paper is not sufficient, such as the phenomenon is likely to occur.
Japanese Patent Application Laid-Open No. 56-147861 Japanese Patent Laid-Open No. 9-111165 US Pat. No. 5,156,675 US Pat. No. 5,183,502 US Pat. No. 5,196,056 U.S. Pat. No. 2,083,372 JP-A-8-319444 Japanese Patent Publication No. 7-94634 JP-A-8-59715 JP-A-5-339516 JP-A-8-302227 JP-A-8-302228 JP-A-8-81647 Japanese Patent Laid-Open No. 8-21815 JP-A-8-295837 JP-A-9-3376 JP-A-8-183920 Japanese Patent Laid-Open No. 10-46075 JP-A-10-292143 Japanese Patent Laid-Open No. 11-80633 JP-A-11-349870 JP 2000-7961 A JP-A-9-31360 JP-A-9-217019 JP 9-316353 A Japanese Patent Laid-Open No. 9-104834 Japanese Patent Laid-Open No. 9-151342 Japanese Patent Laid-Open No. 10-140065 Japanese Patent Laid-Open No. 11-152424 JP-A-11-166145 JP-A-11-166145 Japanese Patent Application Laid-Open No. 11-199783 JP-A-11-209672

The present invention solves the above-mentioned problems, and is excellent in dispersion stability and ejection stability, has no bleeding even on plain paper and recycled paper, and has a high-quality image having high color density and high printing density. An object of the present invention is to provide an inkjet recording ink and a recording method that can be obtained.
Another object of the present invention is to provide an ink for ink jet recording and a recording method capable of obtaining sufficient abrasion resistance not only for plain paper and recycled paper but also for recording media such as coated paper.
Another object of the present invention is to provide an ink for inkjet recording excellent in long-term storage stability.
Another object of the present invention is to provide a recorded matter having a high-quality image having a high printing density and excellent color developability and having sufficient abrasion resistance.
Another object of the present invention is to provide an ink jet recording apparatus that has a high-quality image having a high printing density and excellent color developability, and can obtain a recorded material having sufficient abrasion resistance.

  The present inventors have found that an ink containing a specific compound and a colorant containing a pigment and / or a dye as a polymer and a specific compound has excellent performance as an ink for inkjet recording. Got. In other words, it is excellent in dispersion stability and ejection stability, can be stably printed for a long time without clogging of nozzles, and printed on recording media such as plain paper, recycled paper, and coated paper. In this case, it was found that high-quality images with good printing dryness, no bleeding, high printing density, excellent color development, and excellent scratch resistance can be realized. That is, the present invention is as follows.

[上式中、Ｒは水素原子または炭素数１〜１２の炭化水素基を表し、ｎは２〜２０の数を表し、Ｍはアルカリ金属、アンモニウム塩、またはアルカノールアミンを表す]
５９． 前記重合性界面活性剤が、下記の式（ＩＩ）で表される化合物であることを特徴とする前記５４．〜５７．のいずれかに記載のインクジェット記録用インク。

[上式中、Ｒ’は水素原子または炭素数１〜１２の炭化水素基を表し、ｎは２〜２０の数を表し、Ｍはアルカリ金属、アンモニウム塩、またはアルカノールアミンを表す]
６０． 前記顔料および／または染料を包含するポリマーの溶解性パラメータが１１〜１４ｃａｌ／ｃｍ³の範囲であり、かつ、液性成分の溶解度パラメータと前記ポリマーの溶解性パラメータとの差が１．０ｃａｌ／ｃｍ³以上であることを特徴とする前記１．〜５９．に記載のインクジェット記録用インク。
６１． 前記顔料および／または染料を包含するポリマーの酸価が、２０〜２００ＫＯＨｍｇ／ｇであることを特徴とする前記１．〜６０．のいずれかに記載のインクジェット記録用インク。
６２． 前記顔料および／または染料を包含するポリマーのガラス転移温度が、２５℃以下であることを特徴とする前記１．〜６１．のいずれかに記載のインクジェット記録用インク。
６３． 前記顔料および／または染料を包含するポリマーの成膜温度が、２５℃以下であることを特徴とする前記１．〜６２．のいずれかに記載のインクジェット記録用インク。
６４． 前記顔料および／または染料をポリマーで包含した着色剤に水難溶性物質が含有されたことを特徴とする前記１．〜６３．のいずれかにインクジェット記録用インク。
６５． 前記水難溶性物質の水に対する溶解度が１０重量％以下であることを特徴とする前記６４．に記載のインクジェット記録用インク。
６６． 前記６５．のいずれかに記載のインクジェット記録用インクにおいて、防腐剤と金属イオン捕獲剤と防錆剤とを含有し、該防腐剤がアルキルイソチアゾロン、クロルアルキルイソチアゾロン、ベンズイソチアゾロン、ブロモニトロアルコール、オキサゾリジン系化合物およびクロルキシレノールからなる群から選択された１種以上の化合物であり、該金属イオン捕獲剤がエチレンジアミン酢酸塩であり、該防錆剤がジシクロヘキシルアンモニウムニトラートおよび／またはベンゾトリアゾールであることを特徴とするインクジェット記録用インク。
６７． 前記防腐剤の添加量（Ａ）が０．０１重量％〜０．１重量％であり、前記金属イオン捕獲剤の添加量（Ｂ）が０．０１重量％〜０．５重量％であり、前記防錆剤の添加量（Ｃ）が０．０１重量％〜０．２重量％であり、Ａ＋Ｂ＋Ｃが０．０３重量％〜０．８重量％であることを特徴とする前記６６．に記載のインクジェット記録用インク。
６８． インクの液滴を吐出して、該液滴を記録媒体に付着させて印刷を行う記録方法であって、前記１．〜６７．のいずれかに記載のインクジェット記録用インクを用いることを特徴とする記録方法。
６９． 前記６８．に記載された記録方法によって印刷されたことを特徴とする記録物。
７０． 電気信号に基づいて振動可能な電歪素子が搭載されるとともに、前記電歪素子の振動によって、前記１．〜前記６７．のいずれかに記載のインクジェット記録用インクを吐出できるように構成されたことを特徴とするインクジェット記録装置。 1. A pigment and / or dye containing a colorant including water and water, and selected from the group consisting of acetylene glycol surfactants, acetylene alcohol surfactants, glycol ethers and 1,2-alkylene glycols An ink for inkjet recording, comprising one or more compounds and having a surface tension in the range of 25 mN / m to 45 mN / m.
2. The content of one or more compounds selected from the group consisting of the acetylene glycol surfactant, acetylene alcohol surfactant, glycol ethers and 1,2-alkylene glycol is 0.5 wt% to 30 wt%. %. 2. Ink for ink jet recording described in 1.
3. One or more compounds selected from the group consisting of acetylene glycol surfactants and acetylene alcohol surfactants, and glycol ethers, which contain a colorant including a pigment and / or dye as a polymer, and water And at least one compound selected from the group consisting of 1,2-alkylene glycols.
4). 1. 1% or more of a compound selected from the group consisting of the acetylene glycol surfactant and the acetylene alcohol surfactant is contained in an amount of 5% by weight or less. ~ 3. 2. Ink for ink jet recording described in 1.
5). Contains 5% by weight or less of one or more compounds selected from the group consisting of the acetylene glycol surfactants and acetylene alcohol surfactants, and selected from the group consisting of glycol ethers and 1,2-alkylene glycols 1 or more of the above-mentioned one or more compounds are contained. ~ 4. An ink for ink jet recording according to any one of the above.
6). It contains 0.5% by weight or more of one or more compounds selected from the group consisting of the acetylene glycol surfactants and acetylene alcohol surfactants, and the weight of the compound and the 1,2-alkylene glycol The ratio is 1: 0 to 1:10. ~ 5. An ink for ink jet recording according to any one of the above.
7). One or more compounds selected from the group consisting of the acetylene glycol surfactants and acetylene alcohol surfactants are 2,4-dimethyl-5-hexyn-3-ol, 2,4,7,9- Tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, and the 2,4-dimethyl-5-hexyn-3-ol, the 2,4 , 7,9-tetramethyl-5-decyne-4,7-diol and 3,6-dimethyl-4-octyne-3,6-diol, respectively, have an average of ethyleneoxy group and / or propyleneoxy group 1. One or more compounds selected from the group consisting of those having 30 or less added in 1 above. ~ 6. An ink for ink jet recording according to any one of the above.
8). The glycol ethers are diethylene glycol mono (C 1-8 alkyl) ether, triethylene glycol mono (C 1-8 alkyl) ether, propylene glycol mono (C 1-6 alkyl) ether, dipropylene 1 or a mixture of two or more selected from the group consisting of glycol mono (C 1-6 alkyl) ethers. ~ 7. An ink for ink jet recording according to any one of the above.
9. The above-mentioned 1., wherein the glycol ether is di (tri) ethylene glycol monobutyl ether and / or (di) propylene glycol monobutyl ether. ~ 7. An ink for ink jet recording according to any one of the above.
10. 8. The above (di) propylene glycol monobutyl ether is contained in an amount of 10% by weight or less. 2. Ink for ink jet recording described in 1.
11. The weight of the compound and (di) propylene glycol monobutyl ether is 0.5% by weight or more of one or more compounds selected from the group consisting of the acetylene glycol surfactant and the acetylene alcohol surfactant. 8. The ratio is 1: 0 to 1:10. Or 10. 2. Ink for ink jet recording described in 1.
12 8. The di (tri) ethylene glycol monobutyl ether is contained in an amount of 20% by weight or less. -Said 11. An ink for ink jet recording according to any one of the above.
13. Containing at least 0.5% by weight of one or more compounds selected from the group consisting of the acetylene glycol surfactants and acetylene alcohol surfactants, and the compound and di (tri) ethylene glycol monobutyl ether 8. The weight ratio is 1: 0 to 1:10. -Said 12. 2. Ink for ink jet recording described in 1.
14 The 1,2-alkylene glycol is 1,2- (alkyl having 4 to 10 carbon atoms) diol. -13. An ink for ink jet recording according to any one of the above.
15. 1. The 1,2-alkylene glycol is 1,2-pentanediol and / or 1,2-hexanediol. -14. An ink for ink jet recording according to any one of the above.
16. 15. The above 1,2- (alkyl having 4 to 10 carbon atoms) diol is contained in an amount of 15% by weight or less. Or 15. 2. Ink for ink jet recording described in 1.
17. 1 above. -16. The ink for ink jet recording according to any one of the above, further comprising at least one compound selected from the group consisting of a polyhydric alcohol and a compound represented by the following formula (1): .
Formula (1) R-EOn-POm-M
R is an alkanol group having 4 to 12 carbon atoms, a cycloalkanol group, a phenol group, and / or a naphthol group, and is a straight chain and / or other isomer. EO represents an ethyleneoxy group, PO represents a propyleneoxy group, n and m are repeating units, and represent an average value in the entire system. EO and PO are present in the molecule and the order is not relevant. M is a hydrogen atom, a sulfonate group, a phosphate group and / or a borate group, and the counter ion of the sulfonate group, phosphate group and / or borate group is hydrogen, an alkali metal, an inorganic base and / or an organic amine.
18. N in said Formula (1) is 0-10, m is 1-5, The said 17. 2. Ink for ink jet recording described in 1.
19. 16. The average molecular weight of the compound represented by the formula (1) is 2000 or less, Or 18. 2. Ink for ink jet recording described in 1.
20. The content of the acetylene glycol surfactant is 5% by weight or less, and the ratio of the compound represented by the formula (1) to the acetylene glycol surfactant is 1: 0 to 1: 3. Said 17. ~ 19. An ink for ink jet recording according to any one of the above.
21. The glycol ether is (di) propylene glycol butyl ether monobutyl ether, contains the glycol ether in an amount of 10% by weight or less, and the weight ratio of the compound represented by the formula (1) to the glycol ether is 1: The above-mentioned 17., characterized in that it is 0 to 1:10. -20. An ink for ink jet recording according to any one of the above.
22. The glycol ether is di (tri) ethylene glycol monobutyl ether, the glycol ether is contained in an amount of 20% by weight or less, and the weight ratio of the compound represented by the formula (1) to the glycol ether is 1: The above-mentioned 17., characterized in that it is 0 to 1:10. -20. An ink for ink jet recording according to any one of the above.
23. 16. The weight ratio of the compound represented by the formula (1) and the 1,2-alkylene glycol is 1: 0 to 1:10. -22. An ink for ink jet recording according to any one of the above.
24. 18. The polyhydric alcohol is an alkyl diol having 3 to 12 carbon atoms and / or an alkyl triol having 3 to 12 carbon atoms. -23. An ink for ink jet recording according to any one of the above.
25. 1 above. -24. The ink for ink-jet recording according to any one of the above, further comprising glycerin.
26. 25. The ink for ink jet recording according to the item 1, further comprising a saccharide.
27. 24. Or 25. The ink for ink jet recording according to the item 2, further comprising a compound represented by the following formula (2).
Formula (2) A- (EP) n
A represents a glycerin skeleton, and EP represents an ethyleneoxy group (terminal OH) and / or a propyleneoxy group (terminal OH), but may be an OH group. N is a repeat unit.
28. N in said Formula (2) is 0.5-10, Said 27. 2. Ink for ink jet recording described in 1.
29. 27. The average molecular weight of the compound represented by the formula (2) is 1000 or less. Or 28. 2. Ink for ink jet recording described in 1.
30. 26. The sugar according to the above 26, wherein 80% by weight or more of the sugar is aldose, ketose and / or sugar alcohol having 12 or less carbon atoms. -29. An ink for ink jet recording according to any one of the above.
31. The above-mentioned 1. The dye is an insoluble or hardly soluble dye in water. -30. The ink composition for ink jet recording according to any one of the above.
32. 1. The colorant containing the pigment and / or dye as a polymer is added in an amount of 0.5 wt% to 30 wt%. ~ 31. An ink for ink jet recording according to any one of the above.
33. The colorant is a colorant including a pigment and / or a dye as a polymer, and the content of the polymer is 10% by weight or more based on the total amount of the colorant. ~ 31. An ink for ink jet recording according to any one of the above.
34. The polymer comprising the pigment and / or the dye contains, as a main component, at least one selected from the group consisting of vinyl polymers, polyesters, polyamides, polyimides, silicon-containing polymers, and sulfur-containing polymers. . To 33. An ink for ink jet recording according to any one of the above.
35. 1. The polymer including the pigment and / or the dye is a copolymer of a dispersant having a polymerizable group and a copolymerizable monomer. -34. An ink for ink jet recording according to any one of the above.
36. A colorant including the pigment and / or dye as a copolymer of a dispersant having a polymerizable group and a copolymerizable monomer disperses the pigment and / or dye in water by the dispersant having the polymerizable group. After that, the copolymerized monomer and the polymerization initiator are added and polymerized. -35. An ink for ink jet recording according to any one of the above.
37. 35. The above-mentioned 35. The copolymerizable monomer is a compound having an unsaturated group in its structure. Or 36. 2. Ink for ink jet recording described in 1.
38. 36. The above-mentioned 37. wherein the unsaturated group is selected from the group consisting of vinyl group, allyl group, acryloyl group, methacryloyl group and propenyl group. 2. Ink for ink jet recording described in 1.
39. 35. The above-mentioned 35. The copolymerizable monomer is an electron-accepting monomer. -38. An ink for ink jet recording according to any one of the above.
40. 35. The above-mentioned copolymerizable monomer is selected from the group consisting of fumaric acid diesters, maleic acid diesters, maleimides, and vinylidene cyanide. ~ 39. An ink for ink jet recording according to any one of the above.
41. 1. The polymer including the pigment and / or dye is a polymer having a crosslinked structure. -33. An ink for ink jet recording according to any one of the above.
42. The colorant including the pigment and / or the dye with a polymer having a crosslinked structure makes a phase-inversion emulsification by bringing an organic phase containing at least a polymer having a crosslinking reactive group and a hydrophilic group and a crosslinking agent into contact with an aqueous phase. The pigment is obtained by including a pigment and / or a dye in the polymer and then performing a crosslinking reaction between the polymer and a crosslinking agent. 2. Ink for ink jet recording described in 1.
43. The polymer having a crosslinking reactive group and a hydrophilic group is a vinyl polymer, poly (meth) acrylic acid ester, styrene- (meth) acrylic acid copolymer, polyester, polyamide, polyimide, polyurethane, amino-based polymer. 41. The main component is one or more selected from the group consisting of a polymer, a silicon-containing polymer, a sulfur-containing polymer, a fluorine-containing polymer, and an epoxy resin. Or 42. 2. Ink for ink jet recording described in 1.
44. The hydrophilic group of the polymer having the crosslinking reactive group and the hydrophilic group is selected from the group consisting of a sulfone group, a sulfonic acid group, a carboxyl group, a hydroxyl group, and a salt thereof and a quaternary ammonium salt. 41. The above-mentioned 41. ~ 43. An ink for ink jet recording according to any one of the above.
45. 41. The cross-linking reactive group of the polymer having the cross-linking reactive group and the hydrophilic group is selected from the group consisting of a glycidyl group, an isocyanate group, a hydroxyl group, and an unsaturated hydrocarbon group. -44. An ink for ink jet recording according to any one of the above.
46. 45. The unsaturated hydrocarbon group is selected from the group consisting of a vinyl group, an allyl group, an acryloyl group, a methacryloyl group, a propenyl group, a vinylidene group, and a vinylene group. 2. Ink for ink jet recording described in 1.
47. 42. The above-mentioned 42. wherein the cross-linking agent has at least two functional groups capable of reacting with the cross-linking reactive group of the polymerization having the cross-linking reactive group and the hydrophilic group in the molecule. -46. An ink for ink jet recording according to any one of the above.
48. The functional group of the crosslinking agent is selected from the group consisting of amino group, carboxyl group, hydroxyl group, carboxyl group, mercapto group, glycidyl group, isocyanate group, N-methylol group, N-methylol ether group, and unsaturated hydrocarbon group. 42. The above-mentioned 42. -47. An ink for ink jet recording according to any one of the above.
49. 48. The 48. characterized in that the unsaturated hydrocarbon group is selected from the group consisting of vinyl group, allyl group, acryloyl group, methacryloyl group, propenyl group, vinylidene group, vinylene group. 2. Ink for ink jet recording described in 1.
50. The said crosslinking agent is 0.01-0.1 by weight ratio with respect to the polymer which has the said crosslinking reactive group and a hydrophilic group, The said 42. -49. An ink for ink jet recording according to any one of the above.
51. 42. A reactive surfactant is contained in the organic phase. ~ 50. An ink for ink jet recording according to any one of the above.
52. 41. The polymer having the cross-linked structure is a polymer of a dispersant having a polymerizable group and a cross-linkable monomer. 2. Ink for ink jet recording described in 1.
53. The colorant including a pigment and / or dye in the polymer having a crosslinked structure disperses the pigment and / or dye in water with a dispersant having a polymerizable group, and then at least a crosslinking monomer and a polymerization initiator. 41. It is obtained by adding and polymerizing. Or 52. 2. Ink for ink jet recording described in 1.
54. 35. The surfactant according to 35, wherein the dispersant having a polymerizable group is a polymerizable surfactant containing at least a polymerizable group, a hydrophobic group, and a hydrophilic group in a molecular structure. ~ 40. , 52. -53. An ink for ink jet recording according to any one of the above.
55. 54. The polymerizable group of the polymerizable surfactant is an unsaturated hydrocarbon group. 2. Ink for ink jet recording described in 1.
56. 55. The unsaturated hydrocarbon group is selected from the group consisting of vinyl group, allyl group, acryloyl group, methacryloyl group, propenyl group, vinylidene group and vinylene group. 2. Ink for ink jet recording described in 1.
57. The hydrophilic group of the polymerizable surfactant is selected from the group consisting of a sulfone group, a sulfonic acid group, a carboxyl group, a carbonyl group, a hydroxyl group, and a salt thereof and a quaternary ammonium salt. 54. -56. An ink for ink jet recording according to any one of the above.
58. The polymerizable surfactant is a compound represented by the following formula (I): 54. -57. An ink for ink jet recording according to any one of the above.

[In the above formula, R represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, n represents a number of 2 to 20, and M represents an alkali metal, an ammonium salt, or an alkanolamine]
59. The polymerizable surfactant is a compound represented by the following formula (II): 54. -57. An ink for ink jet recording according to any one of the above.

[In the above formula, R ′ represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, n represents a number of 2 to 20, and M represents an alkali metal, an ammonium salt, or an alkanolamine]
60. The solubility parameter of the polymer including the pigment and / or dye is in the range of 11 to 14 cal / cm ³ , and the difference between the solubility parameter of the liquid component and the solubility parameter of the polymer is 1.0 cal / cm ^{3. The} above 1. -59. 2. Ink for ink jet recording described in 1.
61. 1. The acid value of a polymer including the pigment and / or dye is 20 to 200 KOHmg / g. ~ 60. An ink for ink jet recording according to any one of the above.
62. 1. The glass transition temperature of the polymer including the pigment and / or dye is 25 ° C. or less. ~ 61. An ink for ink jet recording according to any one of the above.
63. 1. The film forming temperature of the polymer containing the pigment and / or dye is 25 ° C. or less. ~ 62. An ink for ink jet recording according to any one of the above.
64. 1. The coloring agent containing the pigment and / or dye as a polymer contains a poorly water-soluble substance. -63. Ink jet recording ink.
65. 64. The solubility in water of the hardly water-soluble substance is 10% by weight or less. 2. Ink for ink jet recording described in 1.
66. 65. In the inkjet recording ink according to any one of the above, the composition contains a preservative, a metal ion scavenger, and a rust preventive agent, the preservative being an alkylisothiazolone, a chloroalkylisothiazolone, a benzisothiazolone, a bromonitroalcohol, an oxazolidine compound, and One or more compounds selected from the group consisting of chlorxylenol, the metal ion scavenger is ethylenediamine acetate, and the rust inhibitor is dicyclohexylammonium nitrate and / or benzotriazole Ink for ink jet recording.
67. The addition amount (A) of the preservative is 0.01 wt% to 0.1 wt%, the addition amount (B) of the metal ion scavenger is 0.01 wt% to 0.5 wt%, 66. The addition amount (C) of the rust inhibitor is 0.01 wt% to 0.2 wt%, and A + B + C is 0.03 wt% to 0.8 wt%. 2. Ink for ink jet recording described in 1.
68. A recording method for performing printing by ejecting ink droplets and attaching the droplets to a recording medium. -67. A recording method using the ink for inkjet recording according to any one of the above.
69. 68. A recorded matter printed by the recording method described in 1.
70. An electrostrictive element that can vibrate based on an electric signal is mounted. To 67 above. An ink jet recording apparatus configured to discharge the ink for ink jet recording according to any one of the above.

The ink for ink jet recording (also simply referred to as “ink”) of the present invention contains a colorant containing a pigment and / or dye in a polymer and water, and also contains an acetylene glycol surfactant and an acetylene alcohol surfactant. It contains one or more compounds selected from the group consisting of an agent, glycol ethers and 1,2-alkylene glycol.
Here, the ink for inkjet recording has a content of one or more compounds selected from the group consisting of acetylene glycol surfactants, acetylene alcohol surfactants, glycol ethers, and 1,2-alkylene glycols, It is preferable to be comprised so that it may become 0.5 to 30 weight%. If it is less than 0.5% by weight, the effect of improving the permeability tends to be insufficient, and the print quality is hardly improved. On the other hand, if it exceeds 30% by weight, it becomes difficult to use due to an increase in viscosity, and even if it is added more than that, there is a tendency that the effect of improving the printing quality is not recognized. More preferably, it is 1 to 15% by weight.

  In particular, the ink of the present invention contains a colorant containing a pigment and / or dye as a polymer and water, and is selected from the group consisting of an acetylene glycol surfactant and an acetylene alcohol surfactant. It is preferable to contain the above compound and one or more compounds selected from the group consisting of glycol ethers and 1,2-alkylene glycol.

  The ink for ink jet recording preferably contains 5% by weight or less of one or more compounds selected from the group consisting of acetylene glycol surfactants and acetylene alcohol surfactants. If it exceeds 5% by weight, the effect of the print quality will reach its peak, and even if it is added, the viscosity will rise and it will be difficult to use, ink will easily adhere to the tip of the head, and the print will be disturbed. A more preferable addition amount is 0.1% by weight to 2% by weight.

  Further, the ink for ink jet recording contains 5% by weight or less of one or more compounds selected from the group consisting of acetylene glycol surfactants and acetylene alcohol surfactants, glycol ethers, and 1, 2 -The form which contains 1 weight% or more of 1 or more types of compounds selected from the group which consists of alkylene glycol can be mentioned preferably.

  The acetylene glycol surfactant and the acetylene alcohol surfactant have the effect of improving the permeability in a small amount. Therefore, for this reason, when one or more compounds selected from the group consisting of an acetylene glycol surfactant and an acetylene alcohol surfactant are contained in the ink in an amount of 0.5% by weight or less, From the viewpoint of improving print quality, it is preferable that at least one compound selected from the group consisting of glycol ethers and 1,2-alkylene glycol is contained in the ink in an amount of 1% by weight or more.

  In addition, when the ink for inkjet recording contains 0.5% by weight or more of one or more compounds selected from the group consisting of acetylene glycol surfactants and acetylene alcohol surfactants, from the viewpoint of print quality The weight ratio of the compound to the 1,2-alkylene glycol is preferably 1: 0 to 1:10. If the amount of 1,2-alkylene glycol added exceeds 10 times that of the acetylene glycol surfactant and / or acetylene alcohol surfactant, not only does the improvement in print quality tend to reach its peak, but conversely The adverse effect of increasing the viscosity of the ink tends to occur.

One or more compounds selected from the group consisting of acetylene glycol surfactants and acetylene alcohol surfactants are 2,4-dimethyl-5-hexyn-3-ol, 2 from the viewpoint of improving printing quality. , 4,7,9-tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, and 2,4-dimethyl-5-hexyne-3 An ethyleneoxy group for each of -ol, the 2,4,7,9-tetramethyl-5-decyne-4,7-diol and the 3,6-dimethyl-4-octyne-3,6-diol; Preferable examples include one or more compounds selected from the group consisting of an average of 30 or less propyleneoxy groups added.
Wherein 2,4-dimethyl-5-hexyn-3-ol, 2,4,7,9-tetramethyl-5-decyne-4,7-diol and 3,6-dimethyl-4-octyne-3, In the case where ethyleneoxy groups and / or propyleneoxy groups are added to each of the 6-diols, if the addition amount of ethyleneoxy groups and / or propyleneoxy groups exceeds 30 on average, the bubbling of the ink is severe. Therefore, the effect of improving the print quality tends to be low, so 30 or less is preferable.
Moreover, when using acetylene alcohol-type surfactant, a dissolution aid can also be used. As a solubilizing agent, 1,3-dimethyl-2-imidazolidinone, 2-pyrrolidone, and N-methyl-2-pyrrolidone are preferable.

  Examples of glycol ethers include diethylene glycol mono (C 1-8 alkyl) ether, triethylene glycol mono (C 1-8 alkyl) ether, propylene glycol mono (C 1-6 alkyl) ether, dipropylene. A glycol mono (C1-C6 alkyl) ether can be mentioned, These can be used as a 1 type, or 2 or more types of mixture.

  Specifically, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-iso-propyl ether, ethylene glycol monobutyl ether, ethylene glycol mono-t-butyl ether, ethylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether (DEGmME) , Diethylene glycol monoethyl ether (DEGmEE), diethylene glycol monopropyl ether (DEGmPE), diethylene glycol mono-iso-propyl ether, diethylene glycol monobutyl ether (DEGmBE), diethylene glycol mono-t-butyl ether, diethylene glycol monopentyl ether (DEGmPeE), diethylene glycol Monohexyl ether (DEGmHE), diethylene glycol monoheptyl ether (DEGmHpE), diethylene glycol monooctyl ether (DEGmOE), triethylene glycol monomethyl ether (TEGmME), triethylene glycol monoethyl ether (TEGmEE), triethylene glycol monopropyl ether (TEGmPE), triethylene glycol monobutyl ether (TEGmBE), triethylene glycol monopentyl ether (TEGmPeE), triethylene glycol monohexyl ether (TEGmHE), triethylene glycol monoheptyl ether (TEGmHpE), triethylene glycol monooctyl ether (TRGmOE), propylene glycol Monomethyl ether (PGmME), propylene glycol monoethyl ether (PGmEE), propylene glycol monopropyl ether (PGmPE), propylene glycol mono-iso-propyl ether, propylene glycol monobutyl ether (PGmBE), propylene glycol mono-t-butyl ether, propylene Glycol monopentyl ether (PGmPeE), propylene glycol monohexyl ether (PGmHE), dipropylene glycol monomethyl ether (DPGmME), dipropylene glycol monoethyl ether (DPGmEE), dipropylene glycol monopropyl ether (DPGmPE), dipropylene glycol mono -Iso-propyl ether, dipropylene glycol mono Examples include butyl ether (DPGmBE), dipropylene glycol monopentyl ether (DPGmPeE), dipropylene glycol monohexyl ether (DPGmHE), etc., but the larger the alkyl group, the higher the hydrophobicity, so methyl, ethyl, propyl, butyl Is suitable for improving the printing quality on plain paper.

In particular, the glycol ethers are preferably di (tri) ethylene glycol monobutyl ether and / or (di) propylene glycol monobutyl ether.
Here, (di) propylene glycol monobutyl ether means propylene glycol monobutyl ether (PGmBE) (solubility parameter δ = 8.9) and / or dipropylene glycol monobutyl ether (DPGmBE) (δ = 8.2). . In addition, di (tri) ethylene glycol monobutyl ether refers to diethylene glycol monobutyl ether (DEGmBE) (δ = 8.96) and / or triethylene glycol monobutyl ether (TEGmBE) (δ = 8.86).

  In order to obtain penetrability suitable for an ink for ink jet recording, (di) propylene glycol monobutyl ether is preferably contained in the ink at 10% by weight or less. If it exceeds 10% by weight, not only the effect of improving the print quality will reach a peak, but also the adverse effect of an increase in viscosity tends to occur. Further, since (di) propylene glycol monobutyl ether is not so water-soluble, if the amount of addition in the ink exceeds 10% by weight, the addition of a dissolution aid tends to be required. More preferably, it is 0.5 to 5% by weight.

  In addition, when the ink for inkjet recording contains 0.5% by weight or more of one or more compounds selected from the group consisting of acetylene glycol surfactants and acetylene alcohol surfactants, from the viewpoint of print quality The weight ratio of the compound to (di) propylene glycol monobutyl ether is preferably 1: 0 to 1:10. When (di) propylene glycol monobutyl ether exceeds 10 times the amount of acetylene glycol surfactant and / or acetylene alcohol surfactant, the effect of improving the printing quality tends to reach its peak. On the other hand, the adverse effect of increased viscosity tends to occur.

  In order to achieve penetrability suitable as an ink for ink jet recording, di (tri) ethylene glycol monobutyl ether is preferably contained in the ink by 20% by weight or less. If it exceeds 20% by weight, not only the effect of improving the printing quality will reach a peak, but also the adverse effect of an increase in viscosity tends to occur. More preferably, it is 0.5 to 10% by weight.

  Further, when the ink for inkjet recording contains 0.5% by weight or more of one or more compounds selected from the group consisting of acetylene glycol surfactants and acetylene alcohol surfactants, from the viewpoint of print quality, The weight ratio of the compound to di (tri) ethylene glycol monobutyl ether is preferably 1: 0 to 1:10. Di (tri) ethylene glycol monobutyl ether is useful for improving the solubility of acetylene glycol surfactants and improving print quality. However, when the addition amount exceeds 10 times, the effect tends to reach its peak. It becomes difficult to use as an ink for inkjet recording.

Examples of 1,2-alkylene glycol include 1,2- (alkyl having 4 to 10 carbon atoms) diol.
In order to obtain penetrability suitable as an ink for ink jet recording, it is preferable that 1,2-alkylene glycol having 4 to 10 carbon atoms is contained in the ink by 15% by weight or less. Among 1,2-alkylene glycols, those having 3 or less carbon atoms have a low effect of improving permeability. On the other hand, when the number of carbon atoms exceeds 10, the water-solubility is low, making it difficult to use in water-soluble inks such as the present invention, and introducing a water-soluble group such as a structure added with an oxyethylene chain or a sulfonic acid group or a phosphoric acid group. Need arises. If the number of carbon atoms is 4 or more, a 1,2-alkylene glycol derivative having a structure in which a water-soluble group is introduced as described above and having 30 or less carbon atoms can be suitably used.
The 1,2-alkylene glycol having 4 to 10 carbon atoms is preferably contained in the ink in an amount of 15% by weight or less. If it exceeds 15% by weight, the improvement in permeability will reach its peak, and not only the effect of improving the printing quality tends to be low, but also the adverse effect of an increase in viscosity tends to occur.

As 1,2-alkylene glycol, 1,2-butanediol (1,2-BD), 1,2-pentanediol (1,2-PeD), 1,2-hexanediol (1,2-HD) 1,2-octanediol, 1,2-decanediol and the like, and 1,2-pentanediol and / or 1,2-butanediol and 1,2-alkylene glycol are effective as they are used as they are. Hexanediol.
The 1,2-pentanediol is particularly preferably contained in the ink in an amount of 3 to 15% by weight. If the weight is less than 3%, the effect of improving the permeability tends to be low. Further, 1,2-hexanediol is particularly preferably contained in an amount of 0.5 to 10% by weight. If it is less than 0.5%, the effect of improving the permeability tends to be low.

Further, the ink for inkjet recording of the present invention preferably further contains one or more compounds selected from the group consisting of polyhydric alcohols and compounds represented by the following formula (1). Stability and ejection stability can be improved.
Formula (1) R-EOn-POm-M
R is an alkanol group having 4 to 12 carbon atoms, a cycloalkanol group, a phenol group, and / or a naphthol group, and is a straight chain and / or other isomer. EO represents an ethyleneoxy group, PO represents a propyleneoxy group, n and m are repeating units, and represent an average value in the entire system. EO and PO are present in the molecule and the order is not relevant. M is a hydrogen atom, a sulfonate group, a phosphate group and / or a borate group, and the counter ion of the sulfonate group, phosphate group and / or borate group is hydrogen, an alkali metal, an inorganic base and / or an organic amine. .

Regarding M of the above formula (1), the alkali metal is lithium, sodium, potassium, etc., the inorganic salt is ammonia, and the organic amine is monoethanolamine, diethanolamine, triethanolamine, mono Isopropanolamine, mono-s-butanolamine and the like can be used.
In the above formula (1), n is preferably 0 to 10, and m is preferably 1 to 5. Since m and n represent average values in the ink system, each molecule is assumed to have a molecular weight distribution, but may be monodispersed.

  These compounds represented by the formula (1) are prepared by adding a target amount of ethylene oxide or propylene oxide under an atmosphere such as an alkali using alcohol as a starting material, or (mono, di, tri ...) propylene glycol or (mono , Di, tri ...) formed by dehydration addition of ethylene glycol, it is not usually monodispersed, but there is no problem using it as a monodisperse through a process such as distillation. However, the content of residual alcohol in the ink is preferably 1% by weight or less. When the amount exceeds 1% by weight, wetting on the nozzle surface of the head is likely to cause printing deterioration, and problems such as the generation of an alcohol odor also occur.

The average molecular weight of the compound represented by the above formula (1) is preferably 2000 or less. When the average molecular weight exceeds 2000, adverse effects such as a decrease in the permeation effect and an increase in the ink viscosity are likely to occur. More preferably, it is 1000 or less, More preferably, it is 500 or less.
Further, when the inkjet recording ink contains 5% by weight or less of an acetylene glycol surfactant, the ratio of the compound represented by the formula (1) to the acetylene glycol surfactant is 1 from the viewpoint of printing quality. : It is preferable that it is 0.1 to 1: 3. Here, examples of acetylene glycol surfactants include the Surfynol series from Air Products (USA) and the Olfin series from Nissin Chemical Industry.
A preferable addition amount of the compound represented by the formula (1) is 0.5% by weight to 30% by weight in the ink.

Further, when the ink for inkjet recording contains 10% by weight or less of (di) propylene glycol monobutyl ether as a glycol ether, the weight ratio of the compound represented by the formula (1) and the glycol ether is 1: 0. .1 to 1:10 is preferable.
Further, when the ink for inkjet recording contains 20% by weight or less of di (tri) ethylene glycol monobutyl ether as a glycol ether, the weight ratio of the compound represented by the formula (1) to the glycol ether is 1: It is preferably 0.1 to 1:10.

In addition, in the ink for inkjet recording, the weight ratio of the compound represented by the formula (1) and 1,2-alkylene glycol is preferably 1: 0.1 to 1:10.
The polyhydric alcohol is preferably an alkyl diol having 3 to 12 carbon atoms and / or an alkyl triol having 3 to 12 carbon atoms. Specifically, 1,2-propanediol (1,2-PD), 1,3-propanediol (1,3-PD), 1,3-butanediol (1,3-BD), 1,4- Butanediol (1,4-BD), 2,3-pentanediol (2,3-PeD), 1,5-pentanediol (1,5-PeD), 2-methyl-2,4-pentanediol, , 6-hexanediol, 2-ethyl-1,3-hexanediol, 1,2,6-hexanetriol and the like are commercially available.

The ink for inkjet recording according to the present invention preferably further contains sugar and glycerin. The combined use of water-soluble and water-retaining glycerin and sugar increases the effect of suppressing moisture evaporation, so that it can prevent ink viscosity increase and ink solidification due to drying at the nozzle tip of the head. Clogging can be prevented more reliably (clogging reliability can be improved), and good ejection stability can be ensured over a long period of time.
Examples of sugars that can be used in the present invention include monosaccharides, oligosaccharides, polysaccharides, and saccharides.

In this case, examples of the sugar include monosaccharides, oligosaccharides, polysaccharides, and glycosides, and there are aldehyde type, ketone type, and sugar alcohol type. Specifically, erythrose, threose, erythrulose, erythritol, arabinose, xylose, ribulose, xylulose, xylitol, glucose, mannose, galactose, talose, fructose, psicose, tagatose, sorbose, sorbitol, mannitol, trehalose, cordobiose, nigrose, maltose , Isomaltose, isotrehalose, sofolose, laminaribiose, cellobiose, gentibiose, multidextrin, linear oligosaccharide, isomaltoligosaccharide, isomerized sugar, genthioligosaccharide, polydextrose, maltitol, fructooligosaccharide, palatinose, palatinose oligosaccharide , Emulsified oligosaccharide, lactitol, lactulose, lactosucrose, galactooligosaccharide, soybean Sugar, xylo-oligosaccharides, chitin-chitosan oligosaccharide, pectin oligosaccharide, agarooligosaccharides, inulooligosaccharide, Paranichitto, reduced starch syrup, carrageenan, alginic acid, pullulan, xanthan gum, gellan gum, and the like curdlan or polydextrose. Among these saccharides, those having a large molecular weight have a high viscosity and limit the addition amount, and therefore monosaccharides and disaccharides having a relatively small molecular weight are preferable. An increase in the amount of polysaccharide added is not preferable because the viscosity increases.
Therefore, 80% by weight or more of the sugar is preferably aldose, ketose and / or sugar alcohol having 12 or less carbon atoms.

  Sugars particularly preferably used in the present invention include glucose, mannose, maltitol, fructose, ribose, xylose, arabinose, lactose, galactose, aldonic acid, glucitol, maltose, cellobiose, sucrose, trehalose, erythritol, maltotriose, Examples include isomaltoligosaccharide, mannitol, sorbitol, fructose, and xylitol. The amount of the saccharide used in the present invention is 0.05% to 30% by weight, and more preferably 3% to 20% by weight. If it is less than 0.05% by weight, the effect of recovering from clogging due to drying and clogging of the ink at the nozzle tip portion of the head is small, and if it exceeds 30% by weight, the viscosity of the ink increases, resulting in poor discharge. This is not preferable because a problem arises in the discharge stability.

In addition, the ink for inkjet recording according to the present invention preferably further contains glycerin and one or more compounds selected from the group consisting of sugar and a compound represented by the following formula (2). In particular, since the color developability of the image can be improved, the print quality can be further improved. Further, it is possible to more reliably prevent ink from clogging in the head (clogging reliability can be improved).
Formula (2) A- (EP) n
A represents a glycerin skeleton, and EP represents an ethyleneoxy group (terminal OH) and / or a propyleneoxy group (terminal OH), but may be an OH group. N is a repeat unit.

Here, n in the above-described formula (2) is preferably 0.5 to 10. When n is less than 0.5, the effect of improving the printing quality is low. However, when used in combination with the aforementioned saccharides, it depends on the amount added, but is not limited to this range, and may be less than 0.5, more than 10 and less than 30.
Further, the repeating unit (EP) represented by n in the above formula (2) is preferably an ethyleneoxy group and / or a propyleneoxy group, and has a molecular weight distribution. (EP) is preferably ethyleneoxy and / or propyleneoxy, particularly when low viscosity is required, ethyleneoxy is used, and when relatively high viscosity is required, propyleneoxy is preferable, and these amounts can be appropriately selected. it can. Further, these additives are preferable since the ink ejection stability is improved.

  The average molecular weight of the compound represented by the above formula (2) is preferably 1000 or less. When the average molecular weight exceeds 1000, it becomes difficult to reliably improve clogging reliability. Moreover, although the weight average molecular weight (Mw) / number average molecular weight (Mn) is preferably 1.5 or more, the degree of molecular weight distribution does not deny less than 1.5.

  As the dye used in the present invention, a dye insoluble or hardly soluble in water is preferably used. Specific examples of the colorant of the present invention include oil-soluble dyes, basic dyes, disperse dyes, vat dyes, sulfur dyes, organic solvent-soluble dyes, and reactive dyes.

  The pigment used in the present invention is not particularly limited, and both inorganic pigments and organic pigments can be used. As the inorganic pigment, metals such as copper oxide, iron oxide and titanium oxide, carbon blacks such as furnace black, lamp black, acetylene black and channel black can be used. Organic pigments include azo pigments (including azo lakes, insoluble azo pigments, condensed azo pigments, chelate azo pigments), polycyclic pigments (phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxane pigments. Thioindigo pigments, isoindolinone pigments, quinofuranone pigments, etc.), dye chelates (basic dye type chelates, acidic dye type chelates, etc.), nitro pigments, nitroso pigments, aniline black, and the like.

  Examples of pigments for black ink include iron oxides such as C.I. I. Pigment Black 11 is a carbon black C.I. I. Pigment Black 7 is an aniline black C.I. I. Pigment Black 1 can be mentioned, and more specifically, the following carbon black is exemplified. That is, No.2300, No.900, MCF88, No.33, No.40, No.45, No.52, MA7, MA8, MA100, No2200B manufactured by Mitsubishi Chemical Co., Ltd. are Raven5750, Raven5250, Raven5000, Raven3500, Raven1255, Raven700 etc. are Cabot's Regal 400R, Regal 330R, Rega l660R, Mogul L, Monarch 700, Monarch 800, Monarch 880, Monarch 900, Monarch 1000, Monarch 1100, Monarch 1300, Monarch 1400 etc. Degussa Color Black FW1, Color Black FW2, Color Black FW2V, Color Black FW18, Color Black FW200, Color Black S150, Color Black S160, Color Black S170, Printex 35, Printex U, Printex V, Printex 140U, Special Black 6, Special Black 5, Special Black 4A, Special Black 4, etc. can be used.

Further, examples of pigments used in yellow ink include C.I. I. Pigment yellow 1 (fast yellow G), 2, 3, 12 (disazo yellow AAA), 13, 14, 16, 17, 24, 34, 35, 37, 42 (yellow iron oxide), 53, 55, 73, 74 75, 81, 83 (disazo yellow HR), 93, 95, 97, 98, 100, 101, 104, 108, 109, 110, 114, 117, 120, 128, 129, 138, 151, 153, 154,
Examples of pigments used in magenta ink include C.I. I. Pigment Red 1, 2, 3, 5, 7, 12, 17, 22 (Brilliant First Scarlet), 23, 31, 38, 48 (Ca), 48 (Mn), 48: 2 (Permanent Red 2B (Ba)) 48: 2 (Permanent Red 2B (Ca)), 48: 3 (Permanent Red 2B (Sr)), 48: 4 (Permanent Red 2B (Mn)), 49: 1, 52: 2, 53: 1, 57 (Ca), 57: 1 (Brilliant Carmine 6B), 60: 1, 63: 1, 63: 2, 64: 1, 81 (Rhodamine 6G rake), 83, 88, 101 (Bengara), 104, 105, 106 , 108 (cadmium red), 112, 114, 122 (quinacridone magenta), 123, 146, 149, 166, 168, 170, 172, 177, 17 8, 179, 184, 185, 190, 193, 202, 209, 219,
Examples of pigments used for cyan ink include C.I. I. Pigment Blue 1, 2, 3, 15 (phthalocyanine blue R), 15: 1, 15: 2, 15: 3 (phthalocyanine blue G), 15: 4, 15: 6 (phthalocyanine blue E), 15:34, 16 17: 1, 22, 56, 60, 63, C.I. I. Vat Blue 4, C.I. I. Vat Blue 60,
Examples of pigments used in green ink include C.I. I. Pigment Green 1, 4, 7, 8, 10, 17, 18, 36,
Etc.

  The pigment particle size is preferably a pigment composed of particles of 0.5 μm or less, more preferably a pigment composed of particles of 0.01 to 0.15 μm.

  The addition amount of the colorant including these pigments and / or dyes as a polymer is preferably 0.5% by weight to 30% by weight, and particularly preferably 1.0% by weight to 12% by weight. When the addition amount is 0.5% by weight or less, it is difficult to ensure the print density, and when the addition amount is 30% by weight or more, the viscosity of the ink increases or the viscosity characteristics tend to be structural viscosity, and the ejection stability tends to deteriorate. Become.

In addition, regarding the colorant including the pigment and / or dye in the polymer, the content of the polymer is preferably 10% by weight or more based on the total amount of the colorant. More preferably, it is 20 weight% or more, More preferably, it is 30 weight% or more. When it is 10% by weight or more, clogging recovery is particularly good, and in the case of color ink (cyan ink, magenta ink, yellow ink, etc.), the transparency of the color to a transparent sheet such as OHP is improved. Even better.
When the content of the polymer in the colorant is less than 10% by weight, the aforementioned acetylene alcohol surfactant, acetylene glycol surfactant, glycol ether, polyhydric alcohol, and the substance represented by the above formula (2) The polymer may partially swell, in which case the polymer may be easily peeled off from the pigment, and the ink may be thickened.

  Hereinafter, the colorant containing a pigment and / or dye as a polymer will be specifically described. The inclusion in the present invention means a state in which the pigment and / or dye is completely encapsulated with a polymer.

Polymers including the aforementioned pigments and / or dyes include polyacrylates, styrene-acrylic acid copolymers, vinyl polymers such as polystyrene (vinyl polymers), polyesters, polyamides, polyimides, silicon-containing polymers, and sulfur-containing polymers. The main component is preferably at least one selected from the group consisting of polymers.
A dispersion in which a normal pigment (not included in a polymer) is dispersed in water with a dispersant is composed of an acetylene glycol surfactant, an acetylene alcohol surfactant, a glycol ether, and 1,2-alkylene glycol. When a compound selected from the group is added, the dispersant is easily detached on the pigment surface, and in some cases, the compound is adsorbed instead of the detached dispersant. As a result, a phenomenon in which printing is disturbed by the dispersant released from the pigment tends to occur. However, if the above-mentioned polymer is used as the polymer including the pigment and / or dye, the above-mentioned phenomenon is unlikely to occur because the polymer can stably include the colorant. Therefore, the coloring including the pigment and / or dye is included in the polymer. By using the agent as the colorant of the ink composition, stable ejection can be obtained and a good image can be obtained.

In a particularly preferred embodiment of the present invention, the above-mentioned polymer is polymerized according to a known polymerization method using a polymerization initiator using monomers and oligomers having an acryloyl group, a methacryloyl group, a vinyl group or an allyl group as a double bond. What was made can be used suitably.
Here, examples of the monomer include styrene, tetrahydrofurfuryl acrylate, butyl methacrylate, (α, 2, 3 or 4) -alkyl styrene, (α, 2, 3 or 4) -alkoxy styrene, 3,4-dimethyl. Styrene, α-phenylstyrene, divinylbenzene, vinylnaphthalene, dimethylamino (meth) acrylate, dimethylaminoethyl (meth) acrylate, dimethylaminopropylacrylamide, N, N-dimethylaminoethyl acrylate, acryloylmorpholine, N, N- Dimethylacrylamide, N-isopropylacrylamide, N, N-diethylacrylamide, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, ethylhexyl (meth) acrylate , Other alkyl (meth) acrylates, methoxydiethylene glycol (meth) acrylate, ethoxy group, propoxy group, butoxy group diethylene glycol or polyethylene glycol (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl Monofunctional such as (meth) acrylate, isobornyl (meth) acrylate, hydroxyalkyl (meth) acrylate, fluorine-containing, chlorine-containing or silicon-containing (meth) acrylate, (meth) acrylamide, maleic acid amide, (meth) acrylic acid, etc. In the case of introducing a cross-linked structure, (mono, di, tri, tetra, poly) ethylene glycol di (meth) acrylate, 1,4-butanediol, 1,5-pentanediol, 1,6-hex Ethylene oxide addition of (meth) acrylate, trimethylolpropane tri (meth) acrylate, glycerin (di, tri) (meth) acrylate, bisphenol A or bisphenol F, such as ethylene diol, 1,8-octanediol and 1,10-decanediol A compound having an acrylic group or a methacryl group such as di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, or the like can be used.

  Polymerization initiators include potassium persulfate and ammonium persulfate, hydrogen persulfate, azobisisobutyronitrile, benzoyl peroxide, dibutyl peroxide, peracetic acid, cumene hydroperoxide, t-butylhydroxyperoxide, paraffin. A general initiator used for radical polymerization such as menthane hydroxyperoxide can be used, but a water-soluble polymerization initiator is preferably used.

  As a method of including a pigment and / or dye by such a polymer, first, a phase inversion emulsification method, an acid folding method, and a forced emulsification method can be exemplified.

  As a specific example of the phase inversion emulsification method, a self-water dispersible resin (self-water dispersible polymer) in which some acid groups are neutralized with a base is dissolved in an organic solvent, and a pigment and / or dye is added to this solution A method of performing phase inversion emulsification by mixing a colored resin solution obtained by dispersion or dissolution and an aqueous medium containing water as an essential component is known. At the time of phase inversion emulsification, particles of the colorant including the pigment and / or dye are generated in the above resin, so that the colorant including the pigment and / or dye is preferably removed by subsequently removing the organic solvent from the aqueous medium. Can get to. Here, as the self-water dispersible resin, a copolymer of (meth) acrylic acid and at least one monomer selected from the group consisting of styrene, substituted styrene, and (meth) acrylic acid ester having an acid value of 20 to 200 KOHmg / g. A polymer can be illustrated suitably.

  As another specific example of the phase inversion emulsification method, polyester is added to a ketone solvent together with a pigment and / or dye, and a neutralizing agent is added to the ketone solution to ionize carboxyl groups in the polyester. A method of phase inversion emulsification by adding water is known. By distilling off the ketone solvent from this mixed solution, a colorant containing a pigment and / or a dye with a polyester can be suitably obtained.

  As an acid folding method, an acidic compound is added to an aqueous dispersion of a pigment and / or dye finely dispersed by a “resin having a carboxyl group neutralized with a basic compound (polymer)”. Examples thereof include a method in which the pH of the aqueous dispersion is made neutral or acidic, thereby making the resin hydrophobic, thereby strongly fixing the resin to the pigment. Next, by adding a basic compound to the aqueous dispersion and neutralizing the carboxyl group of the resin again, an aqueous dispersion of a colorant including a pigment and / or dye with a resin (polymer) can be suitably obtained. it can.

  As a forced emulsification method, a vinyl polymer having a silicon macromer as a copolymer component and a pigment and / or dye are added to an organic solvent, and a neutralizing agent is added to the obtained solution or dispersion. A method of emulsifying by adding water after ionizing a salt-forming group in a vinyl polymer is known, and then a colorant containing a pigment and / or dye in the polymer by distilling off the organic solvent. Can be suitably obtained.

  In addition, examples of the polymer including a pigment and / or a dye include a copolymer of a dispersant having a polymerizable group and a copolymerizable monomer, which will be described in detail later. A colorant including a pigment and / or dye as a copolymer of a dispersant having a polymerizable group and a copolymerizable monomer is used after the pigment and / or dye is dispersed in water by the dispersant having a polymerizable group. It can be suitably obtained by adding a copolymerizable monomer and a polymerization initiator for polymerization.

As inks for ink jet recording, those having a relatively uniform particle size are preferable from the viewpoint of clogging and ejection stability. Therefore, a colorant containing a pigment and / or dye in a polymer is produced by an emulsion polymerization method. It is preferable.
When a pigment is used, the colorant including the pigment as a polymer is dispersed with the dispersant having a polymerizable group, and then polymerized with a monomer copolymerizable with the dispersant (copolymerizable monomer). It is preferable to obtain by carrying out emulsion polymerization in water using an agent.
The colorant containing the dye as a polymer is preferably obtained by emulsion polymerization in which a water-insoluble or hardly-soluble dye such as oil-soluble dye, disperse dye, vat dye, or reactive dye is directly dissolved in the monomer.
Emulsion polymerization can be carried out by a usual method, and the polymerization proceeds with free radicals generated by thermal decomposition of a water-soluble polymerization initiator in the presence of an emulsifier.

The copolymerizable monomer is preferably a compound having an unsaturated group in the structure, and the unsaturated group includes a vinyl group, an allyl group, an acryloyl group, a methacryloyl group, a propenyl group, an acrylamide group, a vinylamide group, and vinylidene. Particularly preferred are those selected from the group consisting of a group and a vinyl group.
More specifically, any copolymerizable monomer can be used as long as it is highly copolymerizable with a dispersant having a polymerizable group, and generally used radical polymerizable monomers are used. it can. As radically polymerizable monomers, radically polymerizable groups such as vinyl groups, allyl groups, acryloyl groups or methacryloyl groups, propenyl groups, acrylamide groups, vinylamide groups, vinylidene groups, vinylene groups, etc. The monomer which contains 1 or more can be mentioned.

  Specific examples of the radical polymerizable monomer include styrene and styrene derivatives such as methyl styrene, dimethyl styrene, chloro styrene, dichloro styrene, prom styrene, P-chloromethyl styrene, dihinylbenzene; acrylic acid, methyl acrylate, ethyl acrylate N-butyl acrylate, butoxyethyl acrylate, benzyl acrylate, phenyl acrylate, phenoxyethyl acrylate, cyclohexyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, acrylic acid Tetrahydrofurfuryl, isobornyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-acryloyloxyethyl succinate Monofunctional acrylic esters such as 2-acryloyloxyethylphthalic acid, caprolactone acrylate, glycidyl acrylate; methacrylic acid, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate, ptoxymethyl methacrylate, Benzyl methacrylate, phenyl methacrylate, phenoxyethyl methacrylate, cyclohexyl methacrylate, dicyclopentanyl methacrylate, dicyclopentenyl methacrylate, dicyclopentenyloxyethyl methacrylate, tetrahydrofurfuryl methacrylate, isobornyl methacrylate, 2-hydroxy Ethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, glycero Monofunctional methacrylates such as methacrylic acid, 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl phthalic acid, caprolactone methacrylate, glycidyl methacrylate; aminoethyl acrylate, aminopropyl acrylate, methylaminoethyl acrylate, acrylic Methylaminopropyl acrylate, ethylaminoethyl acrylate, ethylaminopropyl acrylate, aminoethylamide acrylate, aminopropylamide acrylate, methylaminoethylamide acrylate, methylaminopropylamide acrylate, ethylaminoethylamide acrylate, Acrylic acid ethylaminopropylamide, methacrylic acid amide, aminoethyl methacrylate, aminopropyl methacrylate, methylamino methacrylate Noethyl, methylaminopropyl methacrylate, ethylaminoethyl methacrylate, ethylaminopropyl methacrylate, aminoethylamide methacrylate, aminopropylamide methacrylate, methylaminoethylmethacrylate methacrylate, methylaminopropylamide methacrylate, ethylaminomethacrylate Ethyl amide, ethyl aminopropyl amide methacrylate, hydroxymethyl acrylate, hydroxymethyl methacrylate, N-methylol acrylamide, allyl alcohol, allyl benzene, allyl-3-cyclohexane propionate, 1-allyl-3,4-dimethoxybenzene, Allyl compounds such as allylphenoxyacetate, allylphenylacetate, allylcyclohexane, allyl polycarboxylate; fumaric acid, male Acid, itaconic acid and their esters cheeks; acrylonitrile, methacrylonitrile, maleic anhydride, N- substituted maleimides, include monomers having a radical polymerizable group such as a cyclic olefin.

  In particular, a monomer having a hydrophilic group is preferably used as the copolymerizable monomer, and examples of the monomer having a carboxyl group include acrylic acid, methacrylic acid, crotonic acid, ethacrylic acid, propylacrylic acid, isopropylacrylic acid, and 2 -Acryloyloxyethyl succinic acid, 2-acryloyloxyethyl phthalic acid, 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl phthalic acid, itaconic acid, fumaric acid, maleic acid and the like. Among these, acrylic acid and methacrylic acid are preferable. Examples of the monomer having a sulfonic acid group include 4-styrene sulfonic acid and its salt, vinyl sulfonic acid and its salt, sulfoethyl acrylate and its salt, sulfoethyl methacrylate and its salt, sulfoalkyl acrylate and its salt, sulfoalkyl Methacrylate and its salt, sulfopropyl acrylate and its salt, sulfopropyl methacrylate and its salt, sulfoaryl acrylate and its salt, sulfoaryl methacrylate and its salt, butylacrylamide sulfonic acid and its salt, 2-acrylamido-2-methylpropanesulfone Examples include acids and salts thereof. Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl acrylate, 2-hydroxybutyl methacrylate, and polyethylene glycol 400 acrylate. Polyethylene glycol 400 methacrylate, N-hydroxyethyl acrylate, N-hydroxyethyl methacrylate, and the like. Examples of the monomer having an amide group include acrylamide, methacrylamide, acrylic acid aminopropylamide, methacrylic acid aminopropylamide, acrylic acid aminoethylamide, methacrylic acid aminoethylamide, and vinylpyrrolidone. Examples of the monomer having a phosphone group include phosphoethyl methacrylate.

The polymerizable surfactant represented by the formula (I) which is preferable as a dispersant having a polymerizable group (described in detail later) is a monomer having a high electron donating property. Highly preferred monomers are preferred. Specific examples of the highly electron-accepting monomer include: fumaric acid diesters such as acrylonitrile, fumaronitrile and dibutyl ester of fumaric acid; maleic acid diesters such as maleic acid dibutyl ester; maleimides such as N-phenylmaleimide; As well as vinylidene cyanide and the like. These may be used alone or as a mixture of two or more.
The addition amount of the copolymerizable monomer is preferably in the range of about 2 to 15 molar ratio, more preferably in the range of about 3 to 12 molar ratio with respect to the dispersant having a polymerizable group. The cabcel pigment particles formed by adding 2 mol ratio or more have excellent dispersion stability in an aqueous medium. In addition, when the addition amount is 15 mol ratio or less, the monomer can be sufficiently dissolved in the adsorption layer of the dispersant having a polymerizable group, and the generation of water-insoluble polymer and the relatively ionic repulsion group can be achieved. Since the decrease in the amount of ink can be suppressed, the dispersion stability of the ink can be improved.

  As a polymerization initiator for obtaining a copolymer of a dispersant having a polymerizable group and a copolymerizable monomer, potassium persulfate, ammonium persulfate, sodium persulfate, 2,2-azobis (2-methylpropionamidine) Preferable examples include dihydrochloride and 4,4-azobis (4-cyanovaleric acid).

  In emulsion polymerization, a chain transfer agent can also be used. For example, in addition to t-dodecyl mercaptan, n-dodecyl mercaptan, n-octyl mercaptan, xanthogens such as dimethylxanthogen disulfide, diisobutylxanthogen disulfide, or dipentene, indene, 1,4-cyclohexadiene, dihydrofuran, xanthene, etc. It is done.

  As a method for dispersing the pigment and / or dye in water, a dispersion method such as a method using ultrasonic dispersion, a bead mill, a sand mill, a roll mill or the like can be used. In particular, when a pigment is used, it is preferable to use a dispersing machine such as a bead mill, a sand mill, or a roll mill because the colorant can be made fine particles.

Moreover, as a polymer containing the said pigment and / or dye, the polymer which has a crosslinked structure can be mentioned.
The colorant containing a pigment and / or dye in a polymer having a crosslinked structure used in the present invention is converted using a polymer (polymer) having a crosslinking reactive group and a hydrophilic group. It can be obtained by phase emulsification and further by carrying out a crosslinking reaction with a crosslinking agent.

  Specifically, in a solvent or dispersion obtained by adding a “pigment and / or dye”, a polymer having a crosslinking reactive group and a hydrophilic group, and a crosslinking agent in an organic solvent, a neutralizer and, if necessary, Is a mixture obtained by adding a surfactant (the surfactant is preferably a polymerizable surfactant described in detail later) is used as an organic solvent phase, and either the organic solvent phase or water is stirred. Meanwhile, water is added to the organic solvent phase, or phase inversion emulsification is performed by adding the organic solvent phase into water, so that the “pigment and / or dye” has a crosslinkable reactive group and a hydrophilic group. And an organic phase composed of a polymer having a crosslinking agent and a crosslinking agent. At this time, the catalyst that causes the crosslinking reaction may be added to either the organic solvent phase or the aqueous phase. If the catalyst is oil-soluble, the catalyst is added to the organic solvent phase. It is preferable to add. Next, after performing a crosslinking reaction at a predetermined temperature at which a crosslinking reaction occurs for a predetermined time, the organic solvent is distilled off by a general method such as a distillation method or a vacuum distillation method, and a polymer having a crosslinked structure is used as a coloring material. It is possible to obtain a dispersion liquid in which a colorant including is dispersed in an aqueous phase.

The polymer having a crosslinking reactive group and a hydrophilic group may be any polymer having at least a crosslinking reactive group and a hydrophilic group. For example, a vinyl polymer, a polyacrylic acid ester, a styrene- Acrylic acid copolymer, polyester, polyamide, polyimide, polyurethane, amino-based polymer, silicon-containing polymer, sulfur-containing polymer, fluorine-containing polymer, epoxy-based resin, or a mixture thereof, with a crosslinking reactive group and hydrophilicity And those having a group.
Examples of the hydrophilic group of the polymer having a crosslinking reactive group and a hydrophilic group include a sulfone group, a sulfonic acid group, a carboxyl group, a hydroxyl group, and a salt thereof and a quaternary ammonium salt. It is preferred that it be selected.
Examples of the crosslinking reactive group of the polymer having the crosslinking reactive group and the hydrophilic group include a glycidyl group, an isocyanate group, a hydroxyl group, a carboxyl group, and an unsaturated hydrocarbon group, and are preferably selected from these groups. .
Examples of the unsaturated hydrocarbon group of the polymer having a crosslinking reactive group and a hydrophilic group include a vinyl group, an allyl group, an acryloyl group, a methacryloyl group, a propenyl group, a vinylidene group, and a vinylene group. It is preferred that

  In a preferred embodiment of the present invention, vinyl polymers, poly (meth) acrylic acid esters, and styrene- (meth) acrylic acid copolymers are used as the polymer having a crosslinking reactive group and a hydrophilic group. Such a polymer is a (meth) acrylic acid having one or more hydrophilic groups selected from the group consisting of sulfone groups, sulfonic acid groups, carboxyl groups, hydroxyl groups, and salts thereof and quaternary ammonium salts. An ester monomer, a (meth) acrylic acid ester monomer having a crosslinking reactive group such as a glycidyl group or an isocyanate group, and a monomer copolymerizable with these monomers are t-butyl peroxybenzoate, di-t-butyl. Peroxides such as peroxide, cumene peroxide, acetyl peroxide, benzoyl peroxide, lauroyl peroxide, and azo compounds such as azobisisobutylnitrile, azobis-2,4-dimethylvaleronitrile, azobiscyclohexanecarbonitrile, etc. Aliphatic hydrocarbons in the presence of polymerization initiators System solvent, can be obtained by performing an aromatic hydrocarbon solvent, ester solvent, ketone solvent, alcohol solvent, a solution polymerization in a solvent such as aprotic solvents.

  In the case of solution polymerization, a polymerization chain transfer agent may be further added, for example, octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-hexadecyl mercaptan, n-tetradecyl mercaptan, t-tetradecyl. Mercaptans such as mercaptans; xanthogen disulfides such as dimethylxanthogen disulfide, diethylxanthogen disulfide, diisopropylxanthogen disulfide; thiuram disulfides such as tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide; carbon tetrachloride, ethylene bromide, etc. Halogenated hydrocarbons; hydrocarbons such as pentaphenylethane; and acrolein, methacrolein, allyl alcohol, 2-ethane Ruhexyl thioglycolate, terbinolene, α-terpinene, γ-terpinene, dipentene, α-methylstyrene dimer (2,4-diphenyl-4-methyl-1-pentene is preferably 50 parts by weight or more), and 9, Examples thereof include unsaturated cyclic hydrocarbon compounds such as 10-dihydroanthracene, 1,4-dihydronaphthalene, indene and 1,4-cyclohexadiene; unsaturated heterocyclic compounds such as xanthene and 2,5-dihydrofuran. These may be used alone or in combination of two or more.

  The polymerization is usually carried out at 30 to 100 ° C., preferably 50 to 80 ° C. for 1 to 10 hours, and is appropriately selected depending on the type of radical polymerization initiator, monomer, solvent and the like to be used. The polymerization is preferably performed in an inert gas atmosphere such as nitrogen. After the polymerization, the copolymer can be isolated from the reaction solution by a known method such as reprecipitation or solvent distillation. Further, the obtained copolymer can be purified by repeating reprecipitation or removing unreacted monomers by membrane separation, chromatographic method, extraction method or the like. The weight average molecular weight of the polymer thus obtained is preferably 1000 to 50000, more preferably 1000 to 30000, from the viewpoints of easy inclusion of the coloring material and easy crosslinking.

  Examples of the (meth) acrylic acid ester monomer having a hydrophilic group include an acrylic monomer having a carboxyl group, for example, acrylic acid, methacrylic acid, crotonic acid, ethacrylic acid, propylacrylic acid, isopropylacrylic acid, itaconic acid, fumar An acid etc. are mentioned. Among these, acrylic acid and methacrylic acid are preferable. Examples of the (meth) acrylic monomer having a sulfonic acid group include sulfoethyl methacrylate, butylacrylamidesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, and the like. Examples of the (meth) acrylic monomer having a phosphone group include phosphoethyl methacrylate.

  Examples of the (meth) acrylic acid ester monomer having a crosslinking reactive group include a polymerizable monomer having a blocked isocyanate group, a monomer having an epoxy group, and a monomer having a 1,3-dioxolan-2-one-4-yl group. Can be mentioned. The polymerizable monomer having a blocked isocyanate group can be easily obtained by, for example, subjecting a polymerizable monomer having an isocyanate group such as 2-methacryloyloxyethyl isocyanate to an addition reaction with a known blocking agent. It can also be produced by subjecting a vinyl copolymer having a hydroxyl group and a carboxyl group to an addition reaction of a compound having an isocyanate group and a blocked isocyanate group. Examples of the monomer having an epoxy group include glycidyl (meth) acrylate and (meth) acrylate monomer having an alicyclic epoxy group. Examples of the monomer having a 1,3-dioxolan-2-one-4-yl group include 1,3-dioxolan-2-one-4-ylmethyl (meth) acrylate, 1,3-dioxolan-2-one- 4-ylmethyl vinyl ether and the like can be mentioned.

  Examples of monomers that can be copolymerized with these monomers include the following. For example, methyl acrylate, ethyl acrylate, isopropyl acrylate, acrylic acid-n-propyl, acrylic acid-n-butyl, acrylic acid-t-butyl, acrylic acid-2-ethylhexyl, acrylic acid-n-octyl, acrylic Lauryl acrylate, benzyl acrylate, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, -n-propyl methacrylate, -n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate , Methacrylic acid esters such as methacrylic acid-n-octyl, lauryl methacrylate, stearyl methacrylate, tridecyl methacrylate, benzyl methacrylate; addition reaction products of stearic acid and glycidyl methacrylate; Addition reaction product of (meth) acrylic acid ester monomer having structure; addition reaction product of oxirane compound containing alkyl group having 3 or more carbon atoms and (meth) acrylic acid; styrene, α-methylstyrene, o-methyl Styrene monomers such as styrene, m-methylstyrene, p-methylstyrene, p-tert-butylstyrene; itaconate esters such as benzyl itaconate and ethyl itaconate; maleate esters such as dimethyl maleate and diethyl maleate; Fumarate esters such as dimethyl fumarate and diethyl fumarate; acrylonitrile, methacrylonitrile, vinyl acetate, isobornyl acrylate, isobornyl methacrylate, aminoethyl acrylate, aminopropyl acrylate, methylaminoethyl acrylate, and methyl methacrylate Tylaminopropyl, ethylaminoethyl acrylate, ethylaminopropyl acrylate, aminoethylamide acrylate, aminopropylamide acrylate, methylaminoethylamide acrylate, methylaminopropylamide acrylate, ethylaminoethylamide acrylate, acrylic Ethyl aminopropylamide, methacrylamide, aminoethyl methacrylate, aminopropyl methacrylate, methylaminoethyl methacrylate, methylaminopropyl methacrylate, ethylaminoethyl methacrylate, ethylaminopropyl methacrylate, aminoethylamide methacrylate, Methacrylic acid aminopropylamide, Methacrylic acid methylaminoethylamide, Methacrylic acid methylaminopropylamide, Methacrylic acid ethylamino Tyramide, ethylaminopropylamide methacrylate, hydroxymethyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, hydroxymethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate , N-methylolacrylamide, allyl alcohol and the like.

  The crosslinking agent reacts with the crosslinking reactive group of the polymer having a crosslinking reactive group and a hydrophilic group to crosslink, and the functional group that reacts with the crosslinking reactive group of the polymer is included in the molecular structure. Those having at least two or more are used. When the crosslinking reactive group of the polymer is a glycidyl group, a compound having two or more functional groups of at least one selected from an amino group, a carboxyl group, a hydroxyl group, an N-methylol group, and an N-methylol ether group It is preferable to use, for example, aliphatic amines such as ethyleneamine group, N-aminoethylpiperazine, metaxylenediamine, 1,3-bis (aminomethyl) cyclohexane, polyamide; paramentanediamine, mesophoronediamine, bis ( Cycloaliphatic amines such as 4-amino-3-methylcyclohexyl) methane and 2-ethyl-4-methylimidazole; metaphenylenediamine, 4,4′-diaminodiphenylamine, 4,4′-diaminodiphenylsulfone, dicyandiamide, etc. Aromatic amines; phthalic anhydride, pyromellitic anhydride Nadic anhydride acid anhydrides such as and the like.

  When the crosslinking reactive group of the polymer having a crosslinking reactive group and a hydrophilic group is an isocyanate group, it has two or more functional groups of at least one selected from a carboxyl group, a hydroxyl group, an amino group, and a mercapto group. It is preferable to use a compound, for example, polyether polyol, polytetramethylene ether glycol, alkylene oxide copolymer polyol, epoxy resin modified polyol, lactone polyester polyol, condensation polyester polyol, polycarbonate diol, acrylic polyol, polybutadiene polyol, Polyols such as phosphorus polyols and halogen-containing polyols; polyether polyamines, polytetramethylene ether diamines, alkylene oxide copolymerized polyamines, epoxy-modified polyamines, condensation-based polyesters Polyamines such as terpolyamine, polycarbonate polyamine, acrylic polyamine; polyether polythiol, polytetramethylene ether dithiol, alkylene oxide copolymerized polythiol, epoxy resin modified polythiol, lactone polyester polythiol, condensed polyester polythiol, polycarbonate dithiol, acrylic polythiol, And polythiols such as polybutadiene polythiol, phosphorus-containing polythiol, and halogen-containing polythiol.

When the crosslinking reactive group of the polymer is a hydroxyl group, it is preferable to use a compound having two or more functional groups of at least one selected from a glycidyl group and an isocyanate group.
When the crosslinking reactive group of the polymer is an unsaturated hydrocarbon group, one or more unsaturated hydrocarbons selected from a vinyl group, an allyl group, an acryloyl group, a methacryloyl group, a propenyl group, a vinylidene group, and a vinylene group It is preferable to use a compound having two or more groups. For example, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, allyl acrylate, bis (acryloxyethyl) Hydroxyethyl isocyanurate, bis (acryloxy neopentyl glycol) adipate, 1,3-butylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol dia Relate, propylene glycol diacrylate, polypropylene glycol diacrylate, 2-hydroxy-1,3-diaacryloxypropane, 2,2-bis [4- (acryloxy) phenyl] propane, 2,2-bis [4- (acrylic) Roxyethoxy) phenyl] propane, 2,2-bis [4- (acryloxyethoxy-diethoxy) phenyl] propane, 2,2-bis [4- (acryloxyethoxy-polyethoxy) phenyl] propane, and hydroxybivalate neo Pentyl glycol diacrylate, 1,4-butanediol diacrylate, dicyclopentanyl diacrylate, dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate, ditrimethylolpropane tetraacrylate , Pentaerythritol triacrylate, tetrabromopisphenol A diacrylate, triglycerol diacrylate, trimethylolpropane triacrylate, tris (acryloxyethyl) isocyanurate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate , Tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, propylene glycol dimethacrylate, polypropylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, Neopentyl glycol dimethacrylate, 2-hydroxy-1 , 3-dimethacryloxypropane, 2,2-bis [4 (methacryloxy) phenyl] propane, 2,2-bis [4- (methacryloxyethoxy) phenyl] propane, 2,2-bis [4- (methacrylic) Roxyethoxydiethoxy) phenyl] propane, 2,2-bis [4- (methacryloxyethoxypolyethoxy) phenyl] propane, tetrabromobisphenol A dimethacrylate, dicyclopentanyl dimethacrylate, dipentaerythritol hexamethacrylate, glycerol di Methacrylate, neopentyl glycol dimethacrylate hydroxybivalate, dipentaerythritol monohydroxypentamethacrylate, ditrimethylolpropane tetramethacrylate, pentaerythritol trimethacrylate, pen Pentaerythritol tetramethacrylate, trimethylolpropane triglycidyl Se roll dimethacrylate, trimethylolpropane trimethacrylate, tris (methacryloxyethyl) isocyanurate, allyl methacrylate, divinylbenzene, diallyl phthalate, diallyl terephthalate, diallyl isophthalate, diethylene glycol bis allyl carbonate.

  The crosslinking agent is preferably added to the organic solvent phase in a weight ratio of 0.01 to 0.1 with respect to the polymer having a crosslinking reactive group and a hydrophilic group. If it is less than 0.01, it is not preferable because viscosity increases in the long term, nozzle clogging, poor discharge stability and the like occur. On the other hand, if it exceeds 0.1, the abrasion resistance is lowered and the particle diameter is increased.

  The catalyst used for the crosslinking reaction may be a compound having an effect of causing or promoting the reaction. One or more unsaturated groups selected from the group consisting of an unsaturated hydrocarbon group and a crosslinking agent selected from a vinyl group, an allyl group, an acryloyl group, a methacryloyl group, a propenyl group, a vinylidene group, and a vinylene group. When using a compound having two or more hydrocarbon groups, peroxidation such as t-butyl peroxybenzoate, di-t-butyl peroxide, cumene perhydroxide, acetyl peroxide, benzoyl peroxide, lauroyl peroxide, etc. And oil-soluble radical polymerization initiators such as azo compounds such as azobisisobutylnitrile, azobis-2,4-dimethylvaleronitrile, azobiscyclohexanecarbonitrile, potassium persulfate, ammonium persulfate, sodium persulfate, 2-azobis (2-methylpropionamidine) dihydrochloride, or Any of water-soluble radical polymerization initiator 4,4-azobis (4-cyanovaleric acid) may be used. In addition, the addition amount of a catalyst is determined suitably.

  The organic solvent used for the organic solvent phase is not particularly limited as long as it dissolves at least the polymer having the crosslinking reactive group and the hydrophilic group. Considering the ease of distilling off the organic solvent, a low boiling point organic solvent is preferred. Examples thereof include ketone organic solvents such as acetone and methyl ethyl ketone, ester organic solvents such as ethyl acetate, alcohol organic solvents such as ethanol and isopropyl alcohol, and aromatic hydrocarbon organic solvents such as benzene.

  The polymer having a crosslinking reactive group and a hydrophilic group is appropriately determined in a weight ratio of 0.3 to 1.5 with respect to the pigment and / or dye, but the average particle diameter of the colorant is 400 nm. In the following, it is preferable to adjust and determine such that the water-soluble substance derived from the polymer having a crosslinking reactive group and a hydrophilic group in the aqueous phase after production is preferably not more than 200 nm and not more than 1000 ppm.

A mixed liquid containing at least “polymer having a crosslinking reactive group and a hydrophilic group”, “crosslinking agent”, and “pigment and / or dye” in an organic solvent, Using various dispersing machines such as a roll mill and a sand mill, the polymer having the crosslinking reactive group and the hydrophilic group is dispersed in the dissolved organic solvent phase, and then a crosslinking agent, and in some cases, an oil-soluble polymer. A polymer having a crosslinking reactive group and a hydrophilic group by a method of dissolving a catalyst, or in a state in which a pigment and / or a dye are dispersed in water (for example, a wet cake of a pigment) using various dispersers. Examples of the method include flushing and dispersing in, and then dissolving or dispersing the crosslinking agent and, in some cases, the oil-soluble catalyst. For the purpose of increasing the dispersibility of the pigment, a dispersant or a surfactant is generally used. In the present invention, a reactive surfactant is preferably used. In addition, the reactive surfactant mentioned here is the same as the polymerizable surfactant described later. As the reactive surfactant, one that reacts with a polymer having a crosslinking reactive group and a hydrophilic group or a crosslinking agent is used. As a result, print image deterioration such as bleeding on plain paper, which tends to occur with ink compositions using colorants produced using commonly used dispersants and surfactants, and around the nozzles of the printer head Impaired discharge due to wetness is improved.
In addition, in order to refine | miniaturize the coloring agent obtained, it is preferable to carry out, irradiating an ultrasonic wave in the case of phase inversion emulsification.

Another preferred embodiment of the polymer having a crosslinked structure is a polymer having a crosslinked structure constituted by a copolymer of at least a dispersant having a polymerizable group and a crosslinking monomer.
The polymer having the above-mentioned crosslinked structure naturally includes a polymer obtained by copolymerizing a dispersant having a polymerizable group, a crosslinking monomer, and a monomer copolymerizable with these crosslinking monomers. .
A colorant including a pigment and / or dye in a polymer having a crosslinked structure constituted by a copolymer of at least a dispersant having a polymerizable group and a crosslinking monomer is a fine and stable pigment and / or dye. Refers to the fully encapsulated particle.

  A colorant containing a pigment and / or dye in a polymer having a crosslinked structure constituted by a copolymer of a dispersant having a polymerizable group and a crosslinking monomer comprises various water-soluble organic solvents and water. It is excellent in dispersion stability in an aqueous medium, and particularly comprises a compound selected from acetylene glycol surfactants and acetylene alcohol surfactants used in the present invention, glycol ethers and 1,2-alkylene glycol. It has good dispersion stability in an aqueous medium comprising a compound selected from the group and water. The reason is not clear, but by encapsulating as described above, the inclusion polymer adheres more firmly to the color material than when the dispersant is simply adsorbed to the surface of the color material particles by van der Waals force. This is considered to be due to the fact that the solvent resistance is improved because the inclusion polymer has a crosslinked structure. The above theory is used only for explaining the contents of the present invention, and the scope of the present invention is not limited only by the theory.

As the crosslinkable monomer used in the present invention, any monomer can be used as long as it is highly copolymerizable with the dispersant having a polymerizable group.
As the crosslinkable monomer used in the present invention, a compound having two or more unsaturated hydrocarbon groups selected from vinyl group, allyl group, acryloyl group, methacryloyl group, propenyl group, vinylidene group and vinylene group is used. For example, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, allyl acrylate, bis (acryloxyethyl) hydroxyethyl isocyanurate, bis (acryloxy) Neopentyl glycol) adipate, 1,3-butylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, Bylene glycol diacrylate, polypropylene glycol diacrylate, 2-hydroxy-1,3-diacryloxypropane, 2,2-bis [4- (acryloxy) phenyl] propane, 2,2-bis [4- (acryloxyethoxy) Phenyl] propane, 2,2-bis [4- (acryloxyethoxy diethoxy) phenyl] propane, 2,2-bis [4- (acryloxyethoxy polyethoxy) phenyl] propane, hydroxypentylglycol dipentyl glycoldi Acrylate, 1,4-butanediol diacrylate, dicyclopentanyl diacrylate, dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate, ditrimethylolpropane tetraacrylate, penta Lithritol triacrylate, tetrabromopisphenol A diacrylate, triglycerol diacrylate, trimethylolpropane triacrylate, tris (acryloxyethyl) isocyanurate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene Glycol dimethacrylate, polyethylene glycol dimethacrylate, propylene glycol dimethacrylate, polypropylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol Dimethacrylate, 2-hydroxy-1,3-dimetac Liloxypropane, 2,2-bis [4- (methacryloxy) phenyl] propane, 2,2-bis [4- (methacryloxyethoxy) phenyl] propane, 2,2-bis [4- (methacryloxyethoxydiethoxy) ) Phenyl] propane, 2,2-bis [4- (methacryloxyethoxypolyethoxy) phenyl] propane, tetrabromobisphenol A dimethacrylate, dicyclopentanyl dimethacrylate, dipentaerythritol hexamethacrylate, glycerol dimethacrylate, hydroxybiba Neopentyl glycol dimethacrylate phosphate, dipentaerythritol monohydroxypentamethacrylate, ditrimethylolpropane tetramethacrylate, pentaerythritol trimethacrylate, pentaerythritol Tetramethacrylate, trimethylolpropane triglycidyl Se roll dimethacrylate, trimethylolpropane trimethacrylate, tris (methacryloxyethyl) isocyanurate, allyl methacrylate, divinylbenzene, diallyl phthalate, diallyl terephthalate, diallyl isophthalate, diethylene glycol bis allyl carbonate.

  The addition amount of the crosslinkable monomer is preferably in the range of 0.1 to 20% by weight, more preferably in the range of 0.1 to 10% by weight with respect to the weight of the polymer obtained. When the amount is less than 0.1% by weight, it is not preferable because of an increase in viscosity over a long period of time, clogging of the nozzle, poor discharge stability, and the like. On the other hand, if it exceeds 20% by weight, the desired colorant is hardly obtained, which is not preferable.

  In the present invention, as a monomer that can be copolymerized with a dispersant having a polymerizable group and a crosslinkable monomer, a commonly used radical polymerizable monomer can be used. As the radical polymerizable monomer, a monomer having at least one unsaturated hydrocarbon group such as vinyl group, allyl group, acryloyl group or methacryloyl group, propenyl group, vinylidene group, vinylene group, etc., in the molecule, which is a radical polymerizable group. Can be mentioned. Specific examples of the radical polymerizable monomer include styrene and styrene derivatives such as methyl styrene, dimethyl styrene, chloro styrene, dichloro styrene, prom styrene, P-chloromethyl styrene, dihinylbenzene; acrylic acid, methyl acrylate, ethyl acrylate , N-butyl acrylate, butoxyethyl acrylate, benzyl acrylate, phenyl acrylate, phenoxyethyl acrylate, cyclohexyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, acrylic acid Tetrahydrofurfuryl, isobornyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-acryloyloxyethyl succinate Monofunctional acrylic esters such as 2-acryloyloxyethylphthalic acid, caprolactone acrylate, glycidyl acrylate; methacrylic acid, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate, ptoxymethyl methacrylate, Benzyl methacrylate, phenyl methacrylate, phenoxyethyl methacrylate, cyclohexyl methacrylate, dicyclopentanyl methacrylate, dicyclopentenyl methacrylate, dicyclopentenyloxyethyl methacrylate, tetrahydrofurfuryl methacrylate, iribornyl methacrylate, 2-hydroxy Ethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, glycero Monofunctional methacrylic acid esters such as methyl methacrylate, 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl phthalic acid, cabrolactone methacrylate, glycidyl methacrylate; allylbenzene, allyl-3-cyclohexanepropionate, 1-allyl Allyl compounds such as 3,4-dimethoxybenzene, allylphenoxyacetate, allylphenylacetate, allylcyclohexane, allyl polycarboxylate; fumaric acid, maleic acid, itaconic acid and their ester cheeks; acrylonitrile, methacrylonitrile, maleic anhydride And monomers having a radical polymerizable group such as acid, N monosubstituted maleimide, and cyclic olefin.

  Since the polymerizable surfactant represented by the formula (I), which is preferable as a dispersant having a polymerizable group (described in detail later), is a monomer having a high electron donating property, the monomer used is a monomer having a high electron accepting property. Is preferred. Specific examples of highly electron-accepting monomers include acrylonitrile, fumaronitrile, fumaric acid diesters such as dibutyl ester of fumaric acid; maleic acid diesters such as dibutyl maleate; maleimides such as N-phenylmaleimide; and cyanide Vinylidene chloride and the like. These may be used alone or as a mixture of two or more.

  The addition amount of the monomer is preferably in the range of about 2 to 15 molar ratio, more preferably in the range of about 3 to 12 molar ratio with respect to the dispersant having a polymerizable group. The colorant (Capsule color material particles) formed by setting the addition amount to 2 molar ratio or more is excellent in dispersion stability in an aqueous medium. In addition, when the addition amount is 15 mol ratio or less, the monomer can be sufficiently dissolved in the adsorption layer of the dispersant having a polymerizable group, and the generation of water-insoluble polymer and the relatively ionic repulsion group can be achieved. Therefore, the dispersion stability of the ink composition can be improved.

Production of a colorant including a pigment with a polymer having a crosslinked structure composed of a dispersant having a polymerizable group, a crosslinkable monomer, and a monomer copolymerizable with these monomers is produced as follows. be able to.
Namely, an ultrasonic generator after adding a pigment and / or dye and a dispersant having a polymerizable group to an aqueous organic solvent and / or water and wet-grinding with a disperser such as an ultrasonic wave, a ball mill, or a sand grinder , Transfer to a reaction vessel equipped with a stirrer, a dropping device, a reflux condenser, a thermometer, and a temperature controller, and water and / or the crosslinkable monomer, other copolymerizable monomer and polymerization initiator as necessary. By adding an aqueous organic solvent and carrying out a polymerization reaction at 40 to 100 ° C. for 10 to 60 hours, a colorant including a pigment and / or a dye with a polymer having a crosslinked structure can be obtained. The addition amount of the polymerization initiator is preferably 0.1 to 5% by weight, more preferably 0.1 to 3%, based on the total amount of the dispersant having a polymerizable group and the monomer that can be copolymerized with the crosslinkable monomer. % By weight is preferred. More preferably, it can be produced according to the production method described in JP-A-10-316909.

  As a polymerization initiator for obtaining a polymer having a crosslinked structure, potassium persulfate, sodium persulfate, ammonium persulfate, 2,2-azobis (2-methylpropionamidine) dihydrochloride, or 4,4-azobis ( A water-soluble polymerization initiator such as 4-cyanovaleric acid) is preferably used.

The above-mentioned “dispersant having a polymerizable group” is not particularly limited as long as it contains at least a polymerizable group, a hydrophobic group, and a hydrophilic group in its molecular structure. Polymerizable surfactant containing at least a polymerizable group and a hydrophilic group (in which a polymerizable group is introduced into the surfactant), and at least a polymerizable group, a hydrophobic group, and a hydrophilic group in the molecular structure Preferred examples thereof include a polymer dispersant (in which a polymerizable group is introduced into the polymer dispersant).
The polymerizable group may be a functional group that causes a polymerization reaction such as radical polymerization, polyaddition, and polycondensation. Examples of the radical polymerizable group include unsaturated hydrocarbon groups such as vinyl group, allyl group, acryloyl group, methacryloyl group, vinylidene group and vinylene group. Examples of the polyaddition reactive group include a hydroxyl group, an amino group, a mercapto group, a carboxyl group and the like that react with an isocyanate group or an isothiocyanate group and these groups. The polycondensation reactive group is a functional group capable of a condensation reaction, and examples thereof include a carboxyl group, a hydroxyl group, an amino group, and an alkoxy group.
The polymerizable group is preferably an unsaturated hydrocarbon group that is a radical polymerizable group, and the unsaturated hydrocarbon group is a group consisting of a vinyl group, an allyl group, an acryloyl group, a methacryloyl group, a propenyl group, a vinylidene group, and a vinylene group. It is preferable to select from.
The hydrophilic group is preferably selected from the group consisting of a carboxyl group, a carbonyl group, a hydroxyl group, a sulfone group, a sulfonic acid group and salts thereof, and a quaternary ammonium salt.

  As the polymer dispersant introduced with a polymerizable group, those obtained by introducing a polymerizable group into the following synthetic polymer can be used. Specific examples of synthetic polymers include polyvinyl alcohols: polyvinyl pyrrolidones: polyacrylic acid, acrylic acid-acrylonitrile copolymer, potassium acrylate-acrylonitrile copolymer, vinyl acetate-acrylic ester copolymer Polymers, acrylic resins such as acrylic acid-acrylic acid ester copolymers and their salts: styrene-acrylic acid copolymer, styrene-methacrylic acid copolymer, styrene-methacrylic acid-acrylic acid ester copolymer, styrene -Styrene-acrylic resins such as α-methylstyrene-acrylic acid copolymer and styrene-α-methylstyrene-acrylic acid-acrylic acid ester copolymer and their salts: styrene-maleic acid copolymer, styrene-anhydrous Maleic acid copolymer, vinyl naphthalene-acrylic acid copolymer , Vinyl naphthalene-maleic acid copolymer and salts thereof: and vinyl acetate-ethylene copolymer, vinyl acetate-fatty acid vinyl ethylene copolymer, vinyl acetate-maleic acid ester copolymer, vinyl acetate-crotonic acid copolymer Examples include polymers, vinyl acetate copolymers such as vinyl acetate-acrylic acid copolymers, and salts thereof. Among these, a copolymer of a monomer having a hydrophobic group and a monomer having a hydrophilic group, and a polymer comprising a monomer having both a hydrophobic group and a hydrophilic group in the molecular structure are particularly preferable.

In the present invention, as a preferred embodiment, a polymerizable surfactant is used as a dispersant having a polymerizable group.
The polymerizable surfactant used in the present invention is one in which the hydrophilic group is selected from the group consisting of a sulfone group, a sulfonic acid group, a carboxyl group, a carbonyl group, a hydroxyl group, and salts thereof and a quaternary ammonium salt. In addition, the polymerizable group is an unsaturated hydrocarbon group, and more specifically, selected from the group consisting of a vinyl group, an allyl group, an acryloyl group, a methacryloyl group, a propenyl group, a vinylidene group, and a vinylene group. It is preferable that Specific examples of such polymerizable surfactants include anionic allyl derivatives as described in JP-B-49-46291, JP-B-1-24142, and JP-A-62-104802. Anionic propenyl derivatives as described in JP-A-62-221431, anionic acrylics as described in JP-A-62-34947 and JP-A-55-11525 Acid derivatives, anionic itaconic acid derivatives as described in JP-B-46-34898 and JP-A-51-30284, JP-B-51-4157, JP-A-51-30284 Anionic maleic acid derivatives as described; Nonionic allyl derivatives as described in JP-A-62-104802 Nonionic propenyl derivatives as described in JP-A-62-100502, nonionic acrylic acid derivatives as described in JP-A-56-28208, JP-B-59-12681 Nonionic itaconic acid derivatives as described in JP-A-59-74102; nonionic maleic acid derivatives as described in JP-A-59-74102; And cationic allyl derivatives.
The polymerizable surfactant is adsorbed on the surface of the colorant particles, and is excellent in dispersion stability (that is, it can prevent aggregation between particles) under the subsequent polymerization conditions, so that encapsulated particles are formed. It is advantageous in that it is easy to do.

  In the present invention, the polymerizable surfactant is preferably a compound represented by the following formula (I) or formula (II). By using a polymerizable surfactant represented by the formula (I) or the formula (II), a colorant including a pigment and / or a dye in a polymer can be stabilized as a fine and stable encapsulated particle in an aqueous medium. Can be dispersed. The polymerizable surfactant represented by the formula (I) or the formula (II) is capable of adsorbing the pigment and / or the dye on the surface, and the dispersion stability under the subsequent polymerization conditions (that is, between the particles). It is advantageous in that it is easy to form encapsulated particles. The polymerizable surfactant represented by the formula (I) is disclosed in JP-A-5-320276 and JP-A-10-316909.

[上式中、Ｒは水素原子または炭素数１〜１２の炭化水素基を表し、ｎは２〜２０の数を表し、Ｍはアルカリ金属、アンモニウム塩、またはアルカノールアミンを表す]

[In the above formula, R represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, n represents a number of 2 to 20, and M represents an alkali metal, an ammonium salt, or an alkanolamine]

  By appropriately adjusting the values of R and n in the formula (I), it is possible to correspond to the degree of hydrophilicity or hydrophobicity of the color material surface. Specific examples of preferable polymerizable surfactants represented by the formula (I) include compounds represented by the following formulas (III) to (VI). These may be used alone or as a mixture of two or more.

A commercially available product may be used as the polymerizable surfactant of the formula (I). For example, SE-10N of Adeka Soap SE series of Asahi Denka Co., Ltd., R is C ₉ H ₁₉ , n is 10 and M is NH ₄ , which corresponds to the formula (III). SE-20N is SE-10N where n is 20.

[上式中、Ｒ’は水素原子または炭素数１〜１２の炭化水素基を表し、ｎは２〜２０の数を表し、Ｍはアルカリ金属、アンモニウム塩、またはアルカノールアミンを表す。]
Ｒ’は、Ｃ_９Ｈ_１９−またはＣ_８Ｈ_１７−であることが好ましい。 Moreover, the polymerizable surfactant represented by Formula (II) is as follows.

[In the above formula, R ′ represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, n represents a number of 2 to 20, and M represents an alkali metal, an ammonium salt, or an alkanolamine. ]
R ′ is preferably C ₉ H ₁₉ — or C ₈ H ₁₇ —.

  The polymerizable surfactant can be used in addition to the above commercially available products. For example, Aqualon HS series (Aqualon HS-05, HS-10, HS-20, HS-1025), Aqualon RN series (RN-10, RN-20, RN-30, RN-50) from Daiichi Kogyo Seiyaku Co., Ltd. , RN-2025), New Frontier Series (New Frontier N-177E, S-510), Adeka Soap NE Series from Asahi Denka Co., Ltd. (NE-10, NE-20, NE-30, NE-40, NE-) 50).

The addition amount of the polymerizable surfactant is preferably in the range of about 10 to 150% by weight, more preferably in the range of about 20 to 100% by weight with respect to the pigment and / or dye. By making the addition amount 10% by weight or more, the dispersion stability of the ink composition can be improved.
Moreover, since the addition amount of 150% by weight or less can suppress the generation of a non-adsorbing polymerizable surfactant with the pigment and / or dye, and can prevent the generation of a polymer other than the capsule particles. As a result, the ejection stability of the ink composition can be improved.

  Further, as a colorant including a pigment in a polymer, pigment fine particles encapsulated as described in JP-B-7-94634 or JP-A-8-59715, as described in WO9951690. Examples thereof include pigments having polymer groups bonded to the surface, modified particles having polymer groups having halogen groups as described in US Pat. No. 6,103,380.

Next, a preferable form is shown about the physical property of the polymer containing a pigment and / or dye.
First, the solubility parameter (hereinafter also referred to as “SP _p ”) of the “polymer including the pigment and / or dye” is in the range of 11 to 14 cal / cm ³ , and the solubility parameter of the liquid component is The difference (hereinafter also referred to as “ΔSP”) from the solubility parameter of the polymer is preferably 1.0 cal / cm ³ or more. Here, the liquid component refers to an aqueous mixed liquid (aqueous medium) composed of water and a water-soluble organic solvent.
SP _p, a hydrophilic polymer, represent a hydrophobic, when SP _p is less than 11cal / cm ^3, because the hydrophobicity of the polymer is too high, and include pigments and / or dyes in a polymer colored The dispersibility of the colorant in the aqueous medium is not good, and when the SP _p exceeds 14 cal / cm ³ , the polymer swells in the aqueous medium and the hydration layer is expanded to increase the particle size of the colorant. In some cases, however, an increase in viscosity is observed, and the discharge stability is deteriorated and the nozzles are easily clogged. Therefore, SP _p is preferably in the above range.
When ΔSP is less than 1.0 cal / cm ³ , the mixed solvent permeates into the polymer and the polymer is dissolved or / and swollen, resulting in an increase in viscosity and the like, and storage stability cannot be obtained. Deterioration of discharge stability and nozzle clogging are likely to occur. Therefore, the difference between the solubility parameter of the mixed solvent and the solubility parameter of the polymer is preferably within the above range.

The solubility parameter (δ) is a value obtained by calculating from the following Fedors equation from the evaporation energy (Δe _i ) and the molar volume (Δv _i ) of atoms or atomic groups having a chemical structure.
<Fedors formula>
δ = (ΣΔe _i / ΣΔv _i ) ^1/2
(Yuji Harasaki, Basic Science of Coating (Tsubaki Shoten, 1980), pp. 54-55)
The solubility parameter can also be obtained from calculation from heat of evaporation, calculation from refractive index, calculation from Kauri-butanol value, calculation from surface tension, and the like.

Further, the acid value of “polymer including pigment and / or dye” is preferably in the range of 20 to 200 KOH mg / g, more preferably in the range of 60 to 140 KOH mg / g. In general, the acid value indicates the number of mg of potassium hydroxide required to neutralize free fatty acids contained in 1 g of fats and oils. In the present invention, the number of mg of potassium hydroxide required to neutralize acid groups such as carboxyl groups and sulfonic acid groups contained in 1 g of the polymer is defined as the acid value.
When the acid value of the polymer is less than 20 KOH mg / g, the dispersion stability of the colorant in an aqueous medium is not sufficient, and when the acid value exceeds 200 KOH mg / g, aggregation occurs during the production of the colorant. The above-mentioned range is preferable because of the problem that the hydration layer of the colorant particles is expanded and the discharge stability is deteriorated and the nozzles are easily clogged.

  Moreover, it is preferable that the glass transition temperature of "the polymer containing a pigment and / or dye" is 25 degrees C or less. When printing on a recording medium such as plain paper or a dedicated ink jet recording medium using the ink of the present invention at room temperature, an aqueous medium (consisting of water and / or a water-soluble organic solvent) around the colorant particles according to the present invention is obtained. Colorant particles come close to each other by penetrating into a recording medium such as plain paper or a dedicated medium for ink-jet recording and being removed from the vicinity of the colorant particles. At that time, the glass transition temperature of the particle surface of the colorant particles is reduced. When the temperature is 25 ° C. or lower, the polymer on the particle surface of the colorant particle is fused by the capillary pressure generated in the gap between the colorant particles, and the color material (pigment and / or dye) is enclosed (included) inside. Since the film is formed in the state, the abrasion resistance of the image can be particularly improved.

  Generally, in polymer solids, especially amorphous polymer solids, when the temperature is raised from a low temperature to a high temperature, a state where a large amount of deformation occurs with a small force from a state where a very large force is required for slight deformation (glass state). The temperature at which this phenomenon occurs is called the glass transition temperature. Generally, in the differential heat curve obtained by temperature rise measurement with a differential scanning calorimeter, the intersection of the base line when the tangent line is drawn from the bottom of the endothermic peak toward the end point of the endotherm. Let temperature be the glass transition temperature. In addition, it is known that other physical properties such as elastic modulus, specific heat, and refractive index change abruptly at the glass transition temperature, and it is known that the glass transition temperature is also determined by measuring these physical properties. ing. In this invention, the glass transition temperature obtained by the temperature rising measurement with a thermal scanning calorimeter (DSC) was used.

  In order to form the colorant according to the present invention more preferably at room temperature when printing on a recording medium such as plain paper or a dedicated medium for inkjet recording using the ink of the present invention, “pigments and / or dyes are used. The glass transition temperature of the “including polymer” is more preferably 15 ° C. or lower, and further preferably 10 ° C. or lower. Therefore, the “polymer including pigment and / or dye” is preferably designed so that the glass transition temperature is 25 ° C. or less, more preferably 15 ° C. or less, and further preferably 10 ° C. or less. Is preferred. The glass transition temperature of the polymer can be within the above range by selecting the kind of polymer, the molecular weight, and the like. If it is possible to heat the printed matter at a temperature higher than the glass transition temperature of the “polymer including pigments and / or dyes”, film formation is possible if the glass transition temperature is lower than the heating temperature. For this reason, the glass transition temperature may exceed 25 ° C. However, in this case, it is necessary to attach a heating mechanism to the ink jet recording apparatus, which causes problems such as an increase in the cost of the apparatus. The transition temperature is preferably 25 ° C. or lower.

  In addition, as described above, when the ink of the present invention is printed on a recording medium such as plain paper or a dedicated ink-jet recording medium at room temperature as described above, the surface of the printed portion is formed into a film, and the image has particularly high abrasion resistance. Can be good. In the present invention, the film forming temperature of the ink on the recording medium is preferably 25 ° C. or lower, more preferably 15 ° C. or lower, and further preferably 10 ° C. or lower. The film-forming temperature of the ink of the present invention on the recording medium is an ink-jet recording medium (for example, Super Fine manufactured by Seiko Epson Corporation) in which inorganic particles are coated on a plastic film together with a small amount of binder using an ink-jet printer under an environment of a predetermined temperature. After printing on a 10 mm x 10 mm area with a 100% duty on a special glossy film, etc. and leaving it to stand at a predetermined temperature for 1 hour, use the yellow aqueous fluorescent pen ZEBRA PEN2 (trademark) manufactured by Zebra. Then, rubbing at a speed of 10 mm / sec under a load of 500 g was set to a temperature at which no dirt was generated.

The colorant containing the pigment and / or dye as a polymer preferably contains a poorly water-soluble substance. As the poorly water-soluble substance, it is preferable to use a substance that is generally used as a film forming aid or film forming aid.
Here, the solubility of the poorly water-soluble substance in water is preferably 10% by weight or less. Ink jet recording inks due to the presence of a substance having a low water solubility and a poorly water-soluble substance having a solubility in water of 10% by weight or less in a colorant containing a pigment and / or dye in a polymer. The fixing property to the recording medium is improved. The reason for this is that the glass transition temperature of the polymer can be lowered by containing a poorly water-soluble substance in the polymer of the colorant of the present invention, whereby the film formability of the polymer can be improved. Because.

  The colorant including a pigment and / or dye as a polymer has been described above. The colorant includes an acetylene glycol surfactant, an acetylene alcohol surfactant, a glycol ether, and 1,2-alkylene glycol. By combining with one or more compounds selected from the group, the dispersion stability and ejection stability are excellent, and stable printing can be performed without clogging of the nozzles over a long period of time. In addition, on a recording medium such as plain paper, recycled paper, and coated paper, it is possible to obtain a high-quality image with good dryness after printing, no bleeding, high printing density, and excellent color development.

Generally, when dispersing a pigment in water, a dispersing agent such as a surfactant or a polymer dispersing agent is used. However, since these dispersing agents are only adsorbed to the pigment, they are usually subject to some environmental factors. The dispersant tends to be easily detached from the color material surface.
In contrast, a colorant containing a pigment and / or dye used in the present invention as a polymer, particularly a colorant containing a pigment and / or dye in a polymer (polymer) having a crosslinked structure, has a polymer. Acetylene glycol-based interface used as a penetrating agent because it is more firmly fixed to the pigment and / or dye and is considered to be less likely to be detached from the pigment and / or dye and provides good solvent resistance. The polymer is less liable to be removed from the pigment and / or dye by contact with the activator, acetylene alcohol surfactant, glycol ether and 1,2-alkylene glycol, and the polymer is less likely to swell by the penetrant. Therefore, it has excellent dispersion stability over a long period of time.

In addition, in an ink using a pigment dispersion in which a pigment is dispersed using a dispersant such as a surfactant or a polymer dispersant and having improved permeability, the liquid is generally not adsorbed on the pigment surface from the beginning of dispersion. The content of the pigment is often limited because the viscosity of the ink tends to increase due to the dispersant dissolved therein and the dispersant released from the pigment after dispersion. For this reason, particularly in plain paper and recycled paper, a sufficient printing density cannot be obtained and good color development is often not obtained.
On the other hand, in the colorant according to the present invention, the polymer is firmly fixed to the pigment and / or dye, so that it is not easily detached from the color material, and therefore, the ink viscosity is hardly increased. Therefore, since it is easy to reduce the viscosity of the ink, there is an advantage that a larger amount of colorant can be contained, and a sufficient printing density can be obtained on plain paper or recycled paper. In addition, said reason was used in order to demonstrate the content of this invention to the last, Comprising: The range of this invention is not limited only by the said reason.

The ink for ink jet recording of the present invention preferably further contains a preservative, a metal ion scavenger, and a rust inhibitor. Here, the preservative is preferably one or more compounds selected from the group consisting of alkylisothiazolones, chloroalkylisothiazolones, benzisothiazolones, bromonitroalcohols, oxazolidine compounds and chloroxylenol, and the metal ion scavenger is ethylenediamine Acetates are preferred, and dicyclohexylammonium nitrate and / or benzotriazole are preferably used as the rust inhibitor.
In the present invention, if the above-mentioned preservative, metal ion scavenger and rust preventive agent are contained in the ink jet recording ink of the present invention, other preservatives, metal ion scavenger and rust preventive agent are used in combination. You can also.

As specific examples of the preservatives, for example, alkylisothiazolones containing octylisothiazolone as an active ingredient are commercially available (for example, NS-800H, NS800G, NS-800P: Nagase Chemical Industries, Ltd.). As chloroalkylisothiazolones, those containing chloroisomethylthiazolone as an active ingredient (for example, NS-500W, NS-80D, NS-CG, NS-TM, NS-RS: Nagase Kasei Kogyo Co., Ltd.) are commercially available. . Those containing benzisothiazolone as an active ingredient (for example, Proxel XL-2, Proxel BDN, Proxel BD20, Proxel GXL, Proxel LV, Proxel TN: above Zeneca (UK), Denide BIT, Denide NIPA: above Nagase Chemical Industries, Ltd. ) Commercially available. Those containing bromonitroalcohol as an active ingredient are commercially available (for example, bronopol, Miaside BT, Miaside AS: Nagase Chemical Industries, Ltd.). The thing which uses chlorxylenol as an active ingredient (for example, PCMX: Nagase Chemical Industries Ltd.) is marketed. Further, an oxazolidine compound or a mixture or modified product of these components as an active ingredient may be used depending on the application (for example, NS-BP, Denise BIT-20N, Denise SPB, Sanise HP, Microstat S520, Sanise SK2, Denise) NS-100, Deniside BF-1, Deniside C3H, Saniset 161, Deniside CSA, Deniside CST, Deniside C3, Deniside OMP, Deniside XR-6, Deniside NM, Mordenize N760, Denisat P4, Denisat P-8, Denisat CHR: Nagase Kasei Kogyo Co., Ltd.) is commercially available. Of these, those having an oxazolidine-based compound as an active ingredient, those having chloroisomethylthiazolone as an active ingredient, and those having benzisothiazolone as an active ingredient are highly effective.
In addition, these preservatives are not single components, but composite components using two or more types whose structures are not very similar are preferred because they can suppress resistant bacteria.

As the metal ion scavenger, ethylenediaminetetraacetate is particularly preferable.
As ethylenediaminetetraacetic acid salt, ethylenediaminetetraacetic acid disodium salt, ethylenediaminetetraacetic acid trisodium salt, ethylenediaminetetraacetic acid tetrasodium salt, ethylenediaminetetraacetic acid dipotassium salt, ethylenediaminetetraacetic acid tripotassium salt, ethylenediaminetetraacetic acid tetrapotassium salt, ethylenediamine Examples thereof include diammonium tetraacetate salt, ethylenediaminetetraacetic acid triammonium salt, ethylenediaminetetraacetic acid tetraammonium salt, etc., but for ink jet recording comprising at least a colorant containing the pigment and / or dye of the present invention as a polymer and water. In the ink, ethylenediaminetetraacetic acid disodium salt and ethylenediaminetetraacetic acid dipotassium salt are preferably used.
This ethylenediaminetetraacetate suppresses the degradation of the dispersion stability of the colorant containing the pigment and / or dye according to the present invention due to the influence of a small amount of metal ions present in the ink path in the ink cartridge or head. There is an effect to.
As the rust preventive, dicyclohexylammonium nitrate and / or benzotriazole are effective. These rust preventives are for preventing the metal head from rusting, and are effective for rusted plated surfaces (especially the tip of the nozzle is easily rusted, which causes ink splashes). Easy to bad).

Further, the addition amount (A) of the preservative is 0.01 wt% to 0.1 wt%, and the addition amount (B) of the metal ion scavenger is 0.01 wt% to 0.5 wt%. The addition amount (C) of the rust inhibitor is preferably 0.01 wt% to 0.2 wt%, and A + B + C is preferably 0.03 wt% to 0.8 wt%.
When the addition amount (A) of the preservative is less than 0.01% by weight, the antiseptic effect of the ink is low, and when it exceeds 0.1%, the stability of the colorant in the ink is affected, and the stability of long-term storage is reduced. This is not preferable because it tends to decrease.
In addition, when the addition amount (B) of the metal ion scavenger is less than 0.01% by weight, the ink cartridge having the urethane foam that may contain a trace amount of metal ions in the ink chamber is filled with the ink of the present invention. When used, foreign matter may be generated. On the other hand, if it exceeds 0.5% by weight, the stability of the colorant in the ink tends to be reduced, and long-term storage becomes difficult.
Furthermore, when the addition amount (C) of the rust inhibitor is less than 0.01% by weight, the metal portion of the head, particularly the vicinity of the nozzle tip, tends to rust when the inkjet recording apparatus is used for a long time. On the other hand, if it exceeds 0.2% by weight, the stability of the colorant in the ink tends to be reduced, and long-term storage becomes difficult.

  As described above, the ink for ink jet recording contains a preservative, a metal ion scavenger, and a rust preventive agent, so that the storage stability of the ink is further improved, and stable ejection over a long period of time is ensured. It can be.

  In addition, the ink for inkjet recording in the present invention has a wetting agent, a humectant, a dissolution aid, a penetration control agent, a viscosity for the purpose of ensuring storage stability, preventing clogging, ensuring ejection stability, and ensuring storage stability. Various additives such as a regulator, a pH regulator, a dissolution aid, an antioxidant, an antifungal agent, a corrosion inhibitor, and other metal ion scavengers can be added.

  In order to suppress drying of the ink at the nozzle tip of the head, it is preferable to add the following water-soluble organic solvent having a water-retaining effect as a wetting agent (or humectant). , Ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol having a molecular weight of 2000 or less, propylene glycol, dipropylene glycol, tripropylene glycol, 1,3-propylene glycol, isopropylene glycol, isobutylene glycol, 1,4-butanediol, 1 , 3-butanediol, 1,5-pentanediol, 1,6-hexanediol, mesoerythritol, pentaerythritol and the like. In the present invention, glycerin, ethylene glycol, diethylene glycol, and polyethylene glycol having a molecular weight of 2000 or less are particularly preferably used.

  In addition, as a component that improves the solubility of the ink component, further improves the permeability to a recording medium such as paper, or prevents clogging of the nozzle, it has 1 to 4 carbon atoms such as ethanol, methanol, butanol, propanol, isopropanol, and the like. Alkyl alcohols, formamide, acetamide, dimethyl sulfoxide, sorbit, sorbitan, acetin, diacetin, triacetin, sulfolane and the like, which can be appropriately selected and used.

  Further, in order to further control the permeability, it is possible to add other surfactants to the ink of the present invention. The surfactant to be added is preferably a surfactant having good compatibility with the ink of the present invention, and among the surfactants, those having high permeability and stability are preferable. Examples thereof include amphoteric surfactants and nonionic surfactants. Amphoteric surfactants include lauryldimethylaminoacetic acid betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, coconut oil fatty acid amidopropyldimethylaminoacetic acid betaine, polyoctylpolyaminoethylglycine and other imidazoline derivatives. is there. Nonionic surfactants include polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene dodecyl phenyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene Ethers such as ethylene alkyl ether and polyoxyalkylene alkyl ether, polyoxyethylene oleic acid, polyoxyethylene oleate, polyoxyethylene distearate, sorbitan laurate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquis Esters such as oleate, polyoxyethylene monooleate, polyoxyethylene stearate, etc. Alkyl esters, and the like fluorine-containing surfactants such as perfluoroalkyl carboxylates.

In addition, pH adjusters, amines such as diethanolamine, triethanolamine, propanolamine, morpholine and their modified products, inorganic hydroxides such as potassium hydroxide, sodium hydroxide, lithium hydroxide, ammonium hydroxide, quaternary Examples thereof include ammonium salts (such as tetramethylammonium), carbonates such as potassium carbonate, sodium carbonate, and lithium carbonate, and phosphates.
Other additives include ureas such as urea, thiourea and tetramethylurea, allophanates such as allophanate and methylallohanate, biurets such as biuret, dimethylbiuret and tetramethylbiuret, and L-ascorbic acid and its salts Commercially available antioxidants, ultraviolet absorbers and the like can also be used.

In addition, the ink for inkjet recording of the present invention preferably has a surface tension of 45 mN / m or less, more preferably in the range of 25 to 45 mN / m. When the surface tension exceeds 45 mN / m, it is difficult to obtain a good printed image because the drying property of printing is deteriorated, bleeding is likely to occur, and color bleeding occurs. On the other hand, when the surface tension is less than 25 mN / m, the periphery of the nozzles of the printer head is likely to get wet, so that the ink droplets are likely to be bent. The surface tension can be measured with a commonly used surface tension meter.
The surface tension of the ink can be set within the above range by adjusting the type and composition ratio of each component constituting the ink.

In addition, since the colorant of the ink of the present invention includes a pigment or a dye included in the polymer, the weather resistance such as light resistance and gas resistance of the obtained image is good. Furthermore, according to the colorant of the ink of the present invention, the characteristics of the polymer including the pigment or dye can be designed with a high degree of freedom by selecting a polymerization monomer and other reactants. Various functions (light resistance, gas resistance, coloring property, glossiness, fixing property, etc.) can be provided.
Also, inks in which pigments are dispersed with common dispersants (surfactants, polymer dispersants, etc.) are basically in a state in which the dispersant is only adsorbed to the pigments. The dispersant is easily detached from the pigment, and the viscosity of the ink tends to be unnecessarily increased by such a dispersant. For this reason, the amount of colorant added is usually limited, which makes it difficult to obtain a sufficient color of an image. However, since the colorant containing the pigment and / or dye of the present invention as a polymer is unlikely to be detached from the pigment and / or dye of the polymer, the viscosity of the ink remains even when the colorant is added in a high addition amount. The viscosity of the ink does not increase, and the viscosity of the ink can be easily reduced, and the amount of the colorant added can be increased as compared with the ink in which the pigment is dispersed with a general dispersant, thereby obtaining an image having sufficient color development. Is easy.

  The configuration of the ink for ink jet recording according to the present invention has been described above. The ink set for ink jet recording according to the present invention includes a plurality of inks, and usually combines three or more different colors of ink. Configured. For example, seven kinds of ink compositions comprising four kinds of ink compositions of magenta ink, yellow ink, cyan ink, and black ink, and further comprising two kinds of magenta ink, yellow ink, and cyan ink in two shades of color. It can be set as the structure etc. which combined. Furthermore, orange ink and green ink can be combined with these configurations.

  The ink jet recording ink and ink jet recording ink set of the present invention are excellent in long-term storage stability.

The recording method of the present invention is a recording method for performing printing by ejecting ink droplets and attaching the droplets to a recording medium, wherein the ink for ink-jet recording of the present invention and / or the ink of the present invention is used. An ink set for ink jet recording is used. Here, the recording method is an ink cartridge containing the ink jet recording ink of the present invention (in the case of an ink set including a plurality of ink jet recording inks, each ink jet recording ink is individually contained. Ink cartridges) are mounted on a known ink jet recording apparatus, and printing can be suitably performed on a recording medium.
Here, as the ink jet recording apparatus, an electrostrictive element that can vibrate based on an electric signal is mounted, and the ink for ink jet recording according to the present invention is applied by the vibration of the electrostrictive element or according to the present invention. An ink jet recording apparatus configured to be able to eject ink included in the ink set can be preferably exemplified.
Moreover, as an ink cartridge (accommodating case) for accommodating ink for inkjet recording, a known cartridge can be suitably used.

  According to the ink for ink jet recording, the ink set for ink jet recording, and the recording method of the present invention, the dispersion stability and ejection stability are excellent, and there is no bleeding on plain paper and recycled paper, and the print density is high. A high-quality image with excellent color development can be obtained, and an image having sufficient abrasion resistance can be obtained not only on plain paper and recycled paper but also on recording media such as coated paper.

  Further, since the recorded matter of the present invention is printed by the recording method of the present invention, it has an image having sufficient abrasion resistance not only on plain paper and recycled paper but also on recording media such as coated paper. It is.

  The present invention will be described in detail by the following examples, but the present invention is not limited to the contents of the examples.

<Preparation of Colorant Including Pigment with Polymer (Copolymer) of Dispersant Having Polymerizable Group and Monomer (Copolymerizable Monomer)>
This colorant is equipped with a stirrer, thermometer, temperature controller, reflux condenser, dropping device, etc. after the pigment is well dispersed in an aqueous organic solvent and / or water using a dispersant having a polymerizable group. It was obtained by carrying out a polymerization reaction for a predetermined reaction time at a predetermined reaction temperature in the presence of a polymerization initiator alone or together with another copolymerizable monomer having a polymerizable group in a reaction vessel. The average particle size of the colorant was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop. The glass transition temperature of the colorant polymer was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) manufactured by Seiko Electronics Co., Ltd., and was determined by the method described above.

(Colorant 1-1: Black colorant)
Colorant 1-1 was produced by the same method as in Example 1 described in JP-A-10-316909. 100 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and 60 parts by weight of the polymerizable surfactant Adekariasorb SE-10N (manufactured by Asahi Denka) represented by the formula (IV) in 250 parts by weight of water In addition, it was irradiated with ultrasonic waves, and further subjected to a dispersion treatment for about 2 hours with a sand mill (manufactured by Yaskawa Seisakusho). A dispersion obtained by dispersing carbon black with a polymerizable surfactant was put into a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel. Next, 30 parts by weight of acrylonitrile, 9 parts by weight of styrene, 51 parts by weight of n-butyl acrylate, 10 parts by weight of methacrylic acid, 10 parts by weight of the above-mentioned polymerizable surfactant, 1 part by weight of potassium persulfate and 100 parts by weight of water were previously added. The mixed emulsion was prepared, and this was gradually dripped in said reaction container using the dropping funnel. After completion of the dropping, a polymerization reaction was carried out at 60 ° C. for 48 hours. The obtained colorant dispersion was neutralized with potassium hydroxide to adjust the pH to around 8, and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 (Leeds & Northrup Microtrac UPA 150) manufactured by Leeds & Northrop, the average particle size was 105 nm. Further, when the glass transition temperature of the colorant 1-1 was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the colorant polymer was 10 ° C. It was.

(Colorant 1-2: Cyan colorant)
Carbon black pigment is C.I. I. A dispersion of the desired colorant was obtained in the same manner as (Colorant 1-1) except that Pigment Blue 15: 3 (copper phthalocyanine pigment: manufactured by Clariant) was used. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 85 nm. Further, when the glass transition temperature of the colorant 1-2 was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the polymer of the colorant was 10 ° C. It was.

(Colorant 1-3: Magenta colorant)
Carbon black pigment is C.I. I. A dispersion of the desired colorant was obtained in the same manner as (Colorant 1-1) except that Pigment Red 122 (dimethylquinacridone pigment: manufactured by Clariant) was used. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 90 nm. Further, when the glass transition temperature of the colorant 1-3 was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the colorant polymer was 10 ° C. It was.

(Colorant 1-4: Yellow colorant)
Carbon black pigment is C.I. I. A target colorant dispersion was obtained in the same manner as in the above (Colorant 1-1) except that Pigment Yellow 180 (diketopyrrolopyrrole: Clariant) was used. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 80 nm. In addition, when the glass transition temperature of the colorant 1-4 was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the colorant polymer was 10 ° C. It was.

(Colorant 1-5: Black colorant)
Colorant 1-5 was produced by the same method as in Example 1 described in JP-A-10-316909. 100 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and 60 parts by weight of a polymerizable surfactant Aqualon HS-10 (Daiichi Pharmaceutical Co., Ltd.) represented by the formula (II) are added to 250 parts of water. In addition to the parts by weight, the mixture was irradiated with ultrasonic waves, and further subjected to a dispersion treatment with a sand mill (manufactured by Yasukawa Seisakusho) for about 2 hours. A dispersion obtained by dispersing carbon black with a polymerizable surfactant was put into a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel. Next, 30 parts by weight of acrylonitrile, 9 parts by weight of styrene, 51 parts by weight of n-butyl acrylate, 10 parts by weight of methacrylic acid, 10 parts by weight of the above-mentioned polymerizable surfactant, 1 part by weight of potassium persulfate and 100 parts by weight of water were previously added. The mixed emulsion was adjusted, and this was gradually dripped in said reaction container using the dropping funnel. After completion of the dropping, a polymerization reaction was carried out at 60 ° C. for 48 hours. The obtained colorant dispersion was neutralized with potassium hydroxide to adjust the pH to around 8, and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 110 nm. Further, when the glass transition temperature of the colorant was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the obtained colorant polymer was 10 ° C. It was.

(Colorant 1-6: Cyan colorant)
Carbon black pigment is C.I. I. A dispersion of the desired colorant was obtained in the same manner as (Colorant 1-5) except that Pigment Blue 15: 3 (copper phthalocyanine pigment: manufactured by Clariant) was used. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 90 nm. Further, when the glass transition temperature of the colorant was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the obtained colorant polymer was 10 ° C. It was.

(Colorant 1-7: Magenta colorant)
Carbon black pigment is C.I. I. A dispersion of the desired colorant was obtained in the same manner as (Colorant 1-5) except that Pigment Red 122 (dimethylquinacridone pigment: Clariant) was used. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 95 nm. Further, when the glass transition temperature of the colorant was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the obtained colorant polymer was 10 ° C. It was.

(Colorant 1-8: Yellow colorant)
Carbon black pigment is C.I. I. A dispersion of the desired colorant was obtained in the same manner as (Colorant 1-5) except that Pigment Yellow 180 (diketopyrrolopyrrole: manufactured by Clariant) was used. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 85 nm. Further, when the glass transition temperature of the colorant was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the obtained colorant polymer was 10 ° C. It was.

(Colorant 1-9: Black colorant)
This colorant was prepared by the same method as in Example 1 described in JP-A-10-316909. That is, in a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel, 5 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and the formula (IV) are used. 3 parts by weight of a polymerizable surfactant SE-10N (Asahi Denka) was added to 80 parts by weight of water and dispersed by irradiating with ultrasonic waves for 4 hours. Next, 1.6 parts by weight of acrylonitrile and 0.05 parts by weight of potassium persulfate were further added, and a polymerization reaction was carried out at 60 ° C. for 48 hours. The obtained solution was filtered with a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained.

(Colorant 1-10: Black colorant)
Except for using the polymerizable surfactant AQUALON HS-10 represented by the formula (II) instead of the polymerizable surfactant ADECARIA soap SE-10N (produced by Asahi Denka) represented by the formula (IV) A target colorant dispersion was obtained in the same manner as in the above (Colorant 1-9).

(Colorant 1-11: Cyan colorant)
C. instead of carbon black I. A target colorant dispersion was obtained in the same manner as in the above (Colorant 1-9) except that CI Pigment Blue 15: 3 was used.

(Colorant 1-12: Magenta colorant)
C. instead of carbon black I. A target colorant dispersion was obtained in the same manner as in the above (Colorant 1-9) except that CI Pigment Red 122 was used.

(Colorant 1-13: Magenta colorant)
C. instead of carbon black I. A target colorant dispersion was obtained in the same manner as in the above (Colorant 1-9) except that CI Pigment Red 180 was used.

(Colorant 1-14: Black colorant)
A target colorant dispersion was obtained in the same manner as (Colorant 1-9) except that 2 parts by weight of dibutyl fumarate was used instead of acrylonitrile.

(Colorant 1-15: Black colorant)
5 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and 3 parts by weight of a polymerizable surfactant SE-10N represented by the formula (IV) are added to 80 parts by weight of water. Then, it was irradiated with ultrasonic waves and further dispersed with a sand mill (manufactured by Yaskawa Seisakusho) for about 2 hours. A dispersion obtained by dispersing carbon black with a polymerizable surfactant was put into a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel. Next, 2 parts by weight of 2-hydroxyethyl methacrylate and 0.05 part by weight of potassium persulfate were further added, and a polymerization reaction was carried out at 60 ° C. for 48 hours. The resulting solution was filtered through a 0.4 μm filter and coarsened. Particles were removed. As a result, a target colorant dispersion was obtained.

(Colorant 1-16: Black colorant)
10 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and 6 parts by weight of a polymerizable surfactant SE-10N represented by the formula (IV) are added to 160 parts by weight of water. Then, it was irradiated with ultrasonic waves and further dispersed with a sand mill (manufactured by Yaskawa Seisakusho) for about 2 hours. A dispersion obtained by dispersing carbon black with a polymerizable surfactant was put into a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel. Next, 2 parts by weight of benzyl methacrylate, 2 parts by weight of n-butyl acrylate, 1 part by weight of methacrylic acid, 0.1 part by weight of the above polymerizable surfactant, 0.05 part by weight of potassium persulfate and 10 parts by weight of water were previously added. The mixture was mixed to prepare an emulsion, which was gradually dropped into the reaction vessel using a dropping funnel. After completion of the dropping, a polymerization reaction was carried out at 60 ° C. for 48 hours. The obtained solution was filtered with a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained.

(Colorant 1-17: Black colorant)
10 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and 6 parts by weight of a polymerizable surfactant SE-10N represented by the formula (IV) are added to 160 parts by weight of water. Then, it was irradiated with ultrasonic waves and further dispersed with a sand mill (manufactured by Yaskawa Seisakusho) for about 2 hours. This dispersion was charged into a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel. Next, 1 part by weight of benzyl methacrylate, 2 parts by weight of n-butyl metallate, 1 part by weight of methacrylic acid, 0.1 part by weight of the above-mentioned polymerizable surfactant, 0.05 part by weight of potassium persulfate and 10 parts by weight of water. Were mixed to prepare an emulsion, which was gradually dropped into the above reaction vessel with a dropping funnel. After completion of the dropping, a polymerization reaction was carried out at 60 ° C. for 48 hours. The resulting colorant dispersion was adjusted to about pH 8 with potassium hydroxide and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. The acid value of the obtained colorant was 101 KOH mg / g. The acid value of the colorant can be considered as the acid value of the polymer.

(Colorant 1-18: Black colorant)
10 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and 6 parts by weight of a polymerizable surfactant SE-10N represented by the formula (IV) are added to 160 parts by weight of water. Then, it was irradiated with ultrasonic waves and further dispersed with a sand mill (manufactured by Yaskawa Seisakusho) for about 2 hours. This dispersion is put into a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel. Next, 1 part by weight of benzyl methacrylate, 2 parts by weight of n-butyl metalylate, 3 parts by weight of methacrylic acid, 0.1 part by weight of the polymerizable surfactant, 0.05 part by weight of potassium persulfate and 10 parts by weight of water Were mixed to prepare an emulsion, which was gradually dropped into the above reaction vessel with a dropping funnel. After completion of the dropping, a polymerization reaction was carried out at 60 ° C. for 48 hours. The resulting colorant dispersion was adjusted to about pH 8 with potassium hydroxide and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. The acid value of the obtained colorant was 168 KOH mg / g. The acid value of the colorant can be considered as the acid value of the polymer. The solubility parameter (δ) of the polymer was 11.3. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 110 nm. Further, when the glass transition temperature of the colorant was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the obtained colorant polymer was 17 ° C. It was.

(Colorant 1-19: Black colorant)
10 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and 6 parts by weight of a polymerizable surfactant SE-10N represented by the formula (IV) are added to 160 parts by weight of water. Then, it was irradiated with ultrasonic waves and further dispersed with a sand mill (manufactured by Yaskawa Seisakusho) for about 2 hours. This dispersion was charged into a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel. Next, 2 parts by weight of acrylonitrile, 1 part by weight of acrylamide, 3 parts by weight of n-butyl metalylate, 1 part by weight of methacrylic acid, 0.1 part by weight of the polymerizable surfactant and 0.05 part by weight of potassium persulfate An emulsion was prepared by mixing 10 parts by weight of water, and this was gradually dropped into the above reaction vessel with a dropping funnel. After completion of the dropping, a polymerization reaction was carried out at 60 ° C. for 48 hours. The resulting colorant dispersion was adjusted to about pH 8 with potassium hydroxide and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. The acid value of the obtained colorant was 101 KOH mg / g. The acid value of the colorant can be considered as the acid value of the polymer. The solubility parameter (δ) of the polymer was 13.8. When the average particle size was measured with a laser Doppler type particle size distribution analyzer, Microtrac UPA150, manufactured by Leeds & Northrop, the average particle size was 105 nm. Further, when the glass transition temperature of the colorant was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the obtained colorant polymer was 13 ° C. It was.

(Colorant 1-20: Black colorant)
Carbon black pigment in a reaction vessel equipped with an ultrasonic generator, a stirrer, a dropping device, a water-cooled reflux condenser, a thermometer, and a temperature controller by the same method as in Example 1 described in JP-A-10-316909 5 parts by weight of Raven C (manufactured by Colombian Carbon Co., Ltd.) and 3 parts by weight of polymerizable surfactant Adekaria soap SE-10N (manufactured by Asahi Denka) represented by the formula (IV) In addition to 80 parts, the ultrasonic wave was dispersed for 4 hours. Next, 1.6 parts by weight of acrylonitrile and 0.05 parts by weight of potassium persulfate were further added, and a polymerization reaction was performed at 60 ° C. for 48 hours. The obtained solution was filtered with a 0.4 μm membrane filter to remove coarse particles.
Next, 27 parts by weight of ion exchange water and 0.05 part by weight of sodium lauryl sulfate are further added to the reaction vessel, and further 100 parts by weight of ion exchange water and 0.5 part by weight of potassium persulfate as a polymerization initiator are added. The nitrogen atmosphere was maintained at 70 ° C. Next, after 3 parts by weight of Adeka Soap SE-10N was added and stirred, 15 parts by weight of styrene, 6 parts by weight of tetrahydrofurfuryl methacrylate, 45 parts by weight of n-butyl acrylate and 0.02 parts by weight of t-dodecyl mercaptan were added. The mixed solution added was dropped and reacted, then neutralized with sodium hydroxide to adjust to pH 8, and then filtered through a 0.3 μm filter to obtain a target colorant dispersion. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 105 nm.

(Colorant 1-21: Black colorant containing film forming aid)
Colorant 1-21 was produced in the same manner as in Example 1 described in JP-A-10-316909. 100 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and 60 parts by weight of a polymerizable surfactant SE-10N represented by formula (IV) are added to 250 parts by weight of water. Then, ultrasonic treatment was performed, and further, a dispersion treatment was performed for about 2 hours with a sand mill (manufactured by Yaskawa Seisakusho). A dispersion obtained by dispersing carbon black with a polymerizable surfactant was put into a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel. Next, 30 parts by weight of acrylonitrile, 50 parts by weight of styrene, 15 parts by weight of n-butyl methacrylate, 10 parts by weight of methacrylic acid, 10 parts by weight of the polymerizable surfactant, and Adecoupler MPC-709 (Asahi Denka Co., Ltd.) 15 Part by weight, 1 part by weight of potassium persulfate and 100 parts by weight of water were mixed to prepare an emulsion, which was gradually dropped into the reaction vessel using a dropping funnel. After completion of the dropping, a polymerization reaction was carried out at 60 ° C. for 48 hours. The obtained colorant dispersion was adjusted to about pH 8 with potassium hydroxide and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 105 nm. Further, when the glass transition temperature of the colorant was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the polymer of the colorant 1-21 was 25 ° C. It was.

(Colorant 1-22: Cyan colorant containing film forming aid)
A target colorant dispersion was obtained in the same manner as (Colorant 1-21) except that the carbon black pigment was replaced with Pigment Blue 15: 3 (copper phthalocyanine pigment: manufactured by Clariant). When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 85 nm.

(Colorant 1-23: Magenta colorant containing film forming aid)
A target colorant dispersion was obtained in the same manner as in the above (Colorant 1-21) except that Pigment Red 122 (Dimethylquinacridone Pigment: Clariant) was used instead of the carbon black pigment. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 90 nm.

(Colorant 1-24: Yellow colorant containing film forming aid)
A dispersion of the desired colorant was obtained by the same method as (Colorant 1-21) except that the carbon black pigment was replaced with Pigment Yellow 180 (diketopyrrolopyrrole: manufactured by Clariant). When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 80 nm.

<Preparation of Colorant Including Pigment with Polymer having Crosslinked Structure>
(Colorant 2-1: Black colorant)
84 parts by weight of benzyl methacrylate, 85 parts by weight of n-butyl methacrylate, 35 parts by weight of 2-hydroxyethyl methacrylate, 25 parts by weight of methacrylic acid, 13 parts by weight of glycidyl methacrylate and 20.0 parts by weight of t-hexylperoxy-2-ethylhexanoate A mixture consisting of parts was prepared.
Next, 300 parts by weight of methyl ethyl ketone was charged into a reaction vessel, heated to 75 ° C. with stirring under a nitrogen seal, and then the above mixture was added dropwise over 2 hours. After reacting at temperature for 20 hours, methyl ethyl ketone was distilled off to obtain a polymer (A). As a result of GPC, this polymer (A) had a weight average molecular weight of about 13,000. The acid value of the obtained polymer (A) was 76 KOH mg / g.
50 parts by weight of toluene was added to 6 parts by weight of the polymer (A) produced in (Colorant 2-1) and dissolved, and 20 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) was added to the bead mill. After dispersing using a disperser, 0.3 parts by weight of paramentanediamine was further added to the liquid obtained by filtering the used beads and mixed and dissolved with a stirrer.
Next, 60 parts by weight of ion-exchanged water was dropped into the organic solvent phase and emulsified with stirring and ultrasonic irradiation. This emulsion was subjected to a crosslinking reaction at 80 ° C. for 5 hours after completely removing toluene at 60 ° C. under reduced pressure. Thereafter, the pH was adjusted to around 8 with potassium hydroxide, and the mixture was passed through a 0.4 μm filter to obtain a target colorant dispersion. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 180 nm. The solid content concentration was 30.5%.

(Colorant 2-2: Black colorant)
100 parts by weight of toluene was added to 30 parts by weight of the polymer (A) produced in (Colorant 2-1) and dissolved, and 20 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) was added to the bead mill. After dispersing using a disperser, 1.5 parts by weight of paramentane diamine was further added to the liquid obtained by filtering the used beads, and mixed and dissolved with a stirrer.
Next, 100 parts by weight of ion-exchanged water is dropped into the organic solvent phase and emulsified with stirring and ultrasonic irradiation. This emulsion was subjected to a crosslinking reaction at 80 ° C. for 5 hours after completely removing toluene at 60 ° C. under reduced pressure. Thereafter, the pH was adjusted to around 8 with potassium hydroxide, and the mixture was passed through a 0.4 μm filter to obtain a target colorant dispersion. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 180 nm. The solid content concentration was 34%.
As a result of separating part of the dispersion from the colorant and the liquid phase using a centrifuge and analyzing the liquid phase by GPC, the water-soluble substance derived from the polymer was 600 ppm.

(Colorant 2-3: Cyan colorant)
A mixed solution comprising 84 parts by weight of benzyl methacrylate, 85 parts by weight of n-butyl acrylate, 35 parts by weight of 2-hydroxyethyl methacrylate, 25 parts by weight of methacrylic acid, and 20.0 parts by weight of t-hexylperoxy-2-ethylhexanoate was prepared. Prepared.
Next, 300 parts by weight of methyl ethyl ketone was charged into a reaction vessel, heated to 75 ° C. with stirring under a nitrogen seal, and then the above mixture was added dropwise over 2 hours. The mixture was reacted at a temperature for 20 hours to obtain a polymer solution having a number average molecular weight of 13,000. To this polymer solution, 5 parts by weight of 2-methacryloyloxyethyl isocyanate (Karenz MOI manufactured by Showa Denko), 0.1 part by weight of dibutyltin laurate and 200 ppm of hydroquinone were added, and the mixture was heated again and heated at 70 ° C. for 5 hours. A solution of a polymer (B) having an unsaturated hydrocarbon group as a crosslinking reactive group was obtained by reaction.
50 parts by weight of toluene is added to 30 parts by weight of the polymer (B) and dissolved. I. After adding 20 parts by weight of Pigment Blue 15: 3 and dispersing using a bead mill disperser, 0.3 parts by weight of diethylene glycol dimethacrylate is further added to the solution obtained by filtering the used beads and mixed and dissolved with a stirrer. I let you.
Subsequently, 60 parts by weight of ion-exchanged water in which 1% by weight of potassium persulfate as a polymerization initiator was dissolved was dropped into this organic solvent phase and emulsified while stirring and irradiating with ultrasonic waves. This emulsion was subjected to a crosslinking reaction at 75 ° C. for 10 hours, and toluene was completely removed from the emulsion at 60 ° C. under reduced pressure. Thereafter, the pH was adjusted to around 8 with potassium hydroxide, and the mixture was passed through a 0.4 μm filter to obtain a target colorant dispersion. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 180 nm. The solid content concentration was 30.5%.

(Colorant 2-4: Magenta colorant)
50 parts by weight of toluene was added to 30 parts by weight of the polymer (B) produced in the above (Colorant 2-3) and dissolved; I. 20 parts by weight of Pigment Red 122 and 2 parts by weight of Adeka Soap NE-10 from Asahi Denka Co., Ltd., which is a reactive (or polymerizable) surfactant, were added and dispersed using a bead mill disperser, and then used beads 2 parts by weight of diethylene glycol dimethacrylate was further added to the liquid obtained by filtration and mixed and dissolved with a stirrer.
Next, 60 parts by weight of ion-exchanged water in which 1% by weight of potassium persulfate as a polymerization initiator is dissolved is dropped into the organic solvent phase and emulsified while performing stirring and ultrasonic irradiation. This emulsion was subjected to a crosslinking reaction at 75 ° C. for 10 hours, and toluene was completely removed from the emulsion at 60 ° C. under reduced pressure. Thereafter, the pH was adjusted to around 8 with potassium hydroxide, and the mixture was passed through a 0.4 μm filter to obtain a target colorant dispersion. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 150 nm. The solid content concentration was 30%.

(Colorant 2-5: Black colorant)
85 parts by weight of benzyl methacrylate, 85 parts by weight of n-butyl acrylate, 40 parts by weight of 2-hydroxyethyl methacrylate, 55 parts by weight of methacrylic acid, 15 parts by weight of glycidyl methacrylate and 20.0 parts by weight of t-hexylperoxy-2-ethylhexanoate A mixture consisting of parts was prepared.
Next, 300 parts by weight of methyl ethyl ketone was charged into a reaction vessel, heated to 75 ° C. with stirring under a nitrogen seal, and then the above mixture was added dropwise over 2 hours. After reacting at temperature for 20 hours, methyl ethyl ketone was distilled off to obtain a polymer. As a result of GPC, this polymer had a weight average molecular weight of about 13,000. The acid value of the obtained polymer was 145 KOH mg / g.
50 parts by weight of toluene is added to 6 parts by weight of this polymer and dissolved, 20 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) is added and dispersed using a bead mill disperser, and then the used beads are dispersed. To the liquid obtained by filtration, 0.3 parts by weight of paramentanediamine was further added and mixed and dissolved with a stirrer.
Next, 60 parts by weight of ion-exchanged water was dropped into the organic solvent phase and emulsified with stirring and ultrasonic irradiation. This emulsion was subjected to a crosslinking reaction at 80 ° C. for 5 hours after completely removing toluene at 60 ° C. under reduced pressure. Thereafter, the pH was adjusted to around 8 with potassium hydroxide, and the mixture was passed through a 0.4 μm filter to obtain a target colorant dispersion. The solubility parameter (δ) of the polymer was 11.0. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 180 nm. Further, when the glass transition temperature of the colorant was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the obtained colorant polymer was 21 ° C. It was.

  In addition, a colorant including a pigment in a polymer having a crosslinked structure is prepared by dispersing the pigment well in an aqueous organic solvent and / or water using a dispersant having a polymerizable group, and then stirring, a thermometer, and temperature adjustment. Or by conducting a polymerization reaction for a predetermined reaction time at a predetermined reaction temperature in the presence of a polymerization initiator together with a dispersant having a polymerizable group and a crosslinkable monomer in a reaction vessel equipped with a condenser, a reflux condenser, and a dropping funnel. can get. Below, the example of the coloring agent produced based on this method is shown.

(Colorant 2-6: Black colorant)
Colorant 2-6 was produced in the same manner as in Example 1 described in JP-A-10-316909. 50 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and 30 parts by weight of a polymerizable surfactant SE-10N (manufactured by Asahi Denka) represented by formula (IV) are added to 200 parts by weight of water. The sample was irradiated with ultrasonic waves, and further subjected to a dispersion treatment with a sand mill (manufactured by Yasukawa Seisakusho) for about 2 hours. A dispersion obtained by dispersing the carbon black with a polymerizable surfactant was put into a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel. Next, 16 parts by weight of acrylonitrile, 2.4 parts by weight of divinylbenzene, 1 part by weight of potassium persulfate and 100 parts by weight of water are mixed in advance to prepare an emulsion, which is added to the above reaction vessel using a dropping funnel. The solution was gradually added dropwise. After completion of the dropping, a polymerization reaction was carried out at 60 ° C. for 48 hours. The obtained colorant dispersion was adjusted to a pH of about 8 with potassium hydroxide and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 (Leeds & Northrup Microtrac UPA 150) manufactured by Leeds & Northrop, the average particle size was 110 nm. Further, when the glass transition temperature of the colorant was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the obtained colorant polymer was 20 ° C. It was.

(Colorant 2-7: Black colorant)
Polymerizability represented by the formula (II) instead of the polymerizable surfactant Adekaria soap SE-10N (manufactured by Asahi Denka) represented by the formula (IV) used in the production of the (colorant 2-6). A target colorant dispersion was obtained in the same manner except that the surfactant Aqualon HS-10 was used.

(Colorant 2-8: Magenta colorant)
Colorant 2-8 was produced in the same manner as in Example 1 described in JP-A-10-316909. C. I. 50 parts by weight of Pigment Red 122 and 30 parts by weight of a polymerizable surfactant SE-10N (manufactured by Asahi Denka) represented by the formula (IV) are added to 200 parts by weight of water and irradiated with ultrasonic waves. Dispersion treatment was performed for about 2 hours at Yaskawa Seisakusho. This C.I. I. A dispersion obtained by dispersing Pigment Red 122 with a polymerizable surfactant was put into a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel. Next, 16 parts by weight of acrylonitrile, 5 parts by weight of diallyl isophthalate, 1 part by weight of potassium persulfate and 100 parts by weight of water are mixed in advance to prepare an emulsion, and this is put into the above reaction vessel using a dropping funnel. Slowly dropped. After completion of the dropping, a polymerization reaction was carried out at 60 ° C. for 48 hours. The obtained colorant dispersion was adjusted to a pH of about 8 with potassium hydroxide and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 (Leeds & Northrup Microtrac UPA 150) manufactured by Leeds & Northrop, the average particle size was 115 nm.

(Colorant 2-9: Cyan colorant)
In a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel, C.I. I. 50 parts by weight of Pigment Blue 15: 3 and 30 parts by weight of a polymerizable surfactant SE-10N (produced by Asahi Denka) represented by the formula (IV) are added to 300 parts by weight of water and irradiated with ultrasonic waves for 4 hours. And dispersed. Subsequently, 16 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 3 parts by weight of acrylonitrile, 5 parts by weight of divinylbenzene and 0.5 parts by weight of potassium persulfate were further added, and a polymerization reaction was carried out at 60 ° C. for 48 hours. . Thereafter, the pH is adjusted to around 8 with potassium hydroxide and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained.

(Colorant 2-10: Black colorant)
In a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel, 50 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and polymerization represented by the formula (IV) 30 parts by weight of the surfactant SE-10N (Asahi Denka) was added to 800 parts by weight of water and dispersed by applying ultrasonic waves for 4 hours. Next, 16 parts by weight of acrylonitrile, 2.4 parts by weight of divinylbenzene, 5 parts by weight of fumaric acid and 0.5 parts by weight of potassium persulfate were further added, and a polymerization reaction was carried out at 60 ° C. for 48 hours. Thereafter, the pH was adjusted to around 8 with potassium hydroxide, and the coarse particles were removed by filtration through a 0.4 μm filter. As a result, a target colorant dispersion was obtained. The acid value of the obtained colorant was 126 KOHmg / g.

(Colorant 2-11: Black colorant)
In a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel, 50 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and polymerization represented by the formula (IV) 30 parts by weight of the surfactant SE-10N (Asahi Denka) was added to 800 parts by weight of water and dispersed by applying ultrasonic waves for 4 hours. Next, 16 parts by weight of acrylonitrile, 2.4 parts by weight of divinylbenzene and 0.5 parts by weight of potassium persulfate were further added, and a polymerization reaction was carried out at 60 ° C. for 48 hours. Thereafter, the pH is adjusted to around 8 with potassium hydroxide and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. The acid value of the obtained colorant was 45 KOH mg / g. The solubility parameter (δ) of the polymer was 13.7.

(Colorant 2-12: Black colorant)
In a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel, 50 parts by weight of carbon black (Raven C: manufactured by Columbian Carbon Co., Ltd.) and polymerization represented by the formula (IV) 30 parts by weight of the surfactant SE-10N (Asahi Denka) was added to 800 parts by weight of water and dispersed by applying ultrasonic waves for 4 hours. Next, 16 parts by weight of acrylonitrile, 2.4 parts by weight of divinylbenzene, 3 parts by weight of fumaric acid and 0.5 parts by weight of potassium persulfate were further added, and a polymerization reaction was carried out at 60 ° C. for 48 hours. Thereafter, the pH was adjusted to around 8 with potassium hydroxide, and the coarse particles were removed by filtration through a 0.4 μm filter. As a result, a target colorant dispersion was obtained. The acid value of the obtained colorant was 95 KOH mg / g. The solubility parameter (δ) of the polymer was 13.9.

(Colorant 2-13: Magenta colorant)
C. I. 10 parts by weight of Pigment Red 122 and 6 parts by weight of a polymerizable surfactant SE-10N (produced by Asahi Denka) represented by the formula (IV) are added to 160 parts by weight of water and irradiated with ultrasonic waves. Disperse for about 2 hours with Yaskawa Seisakusho. This dispersion was charged into a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel. Subsequently, 1 part by weight of benzyl methacrylate, 2 parts by weight of n-butyl metalylate, 0.2 part by weight of dicyclopentanyl dimethacrylate, 1 part by weight of methacrylic acid and 0.1 part by weight of the above-mentioned polymerizable surfactant were previously added. An emulsion was prepared by mixing 0.05 part by weight of potassium sulfate and 10 parts by weight of water, and this was gradually dropped into the above reaction vessel with a dropping funnel. After completion of the dropping, a polymerization reaction was carried out at 60 ° C. for 48 hours. The resulting colorant dispersion was adjusted to about pH 8 with potassium hydroxide and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. The acid value of the obtained colorant was 100 KOH mg / g.

(Colorant 2-14: Magenta colorant)
C. I. 10 parts by weight of Pigment Red 122 and 6 parts by weight of a polymerizable surfactant SE-10N (produced by Asahi Denka) represented by the formula (IV) are added to 160 parts by weight of water and irradiated with ultrasonic waves. (Manufactured by Yaskawa Seisakusho) and dispersed for about 2 hours. This dispersion was charged into a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel. Then, in advance, 1 part by weight of benzyl methacrylate, 2 parts by weight of n-butyl metallate, 0.2 part by weight of 1,6-hexanediol dimethacrylate, 2 parts by weight of methacrylic acid and 0.1 part by weight of the above polymerizable surfactant And 0.05 part by weight of potassium persulfate and 10 parts by weight of water were mixed to prepare an emulsion, which was gradually dropped into the above reaction vessel with a dropping funnel. After completion of the dropping, a polymerization reaction was carried out at 60 ° C. for 48 hours. The resulting colorant dispersion was adjusted to about pH 8 with potassium hydroxide and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. The acid value of the obtained colorant was 165 KOH mg / g.
The solubility parameter (δ) of the polymer was 11.0.

(Colorant 2-15: Cyan colorant)
In a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel, C.I. I. Pigment Blue 15: 3 is added to 50 parts by weight and 30 parts by weight of a polymerizable surfactant SE-10N (produced by Asahi Denka) represented by the formula (IV) in 800 parts by weight of water and irradiated with ultrasonic waves for 4 hours. And dispersed. Subsequently, 16 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 3 parts by weight of acrylonitrile, 5 parts by weight of divinylbenzene and 0.5 parts by weight of potassium persulfate were further added, and a polymerization reaction was carried out at 60 ° C. for 48 hours. . The resulting colorant dispersion was adjusted to about pH 8 with potassium hydroxide and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. The acid value of the obtained colorant was 98 KOH mg / g.

(Colorant 2-16: Cyan colorant)
In a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel, C.I. I. 50 parts by weight of Pigment Blue 15: 3 and 20 parts by weight of a polymerizable surfactant SE-10N (produced by Asahi Denka) represented by the formula (IV) were added to 800 parts by weight of water and irradiated with ultrasonic waves for 4 hours. And dispersed. Next, 12 parts by weight of acrylonitrile, 30 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 45 parts by weight of benzyl methacrylate, 45 parts by weight of n-butyl methacrylate, and 0.5 parts by weight of potassium persulfate were further added to the mixture at 60 ° C. The polymerization reaction was carried out for 48 hours. The resulting colorant dispersion was adjusted to about pH 8 with potassium hydroxide and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. The acid value of the obtained colorant was 137 KOH mg / g. The solubility parameter (δ) of the polymer was 11.1.

<Preparation of Colorant Including Dye with Polymer (Copolymer) of Dispersant Having Polymerizable Group and Monomer (Copolymerizable Monomer)>
Examples of colorants using disperse dyes as dyes are shown below, but any dye that is insoluble in water can be preferably used. Oil-soluble dyes, vat dyes, sulfur dyes, organic solvent-soluble dyes, reactive dyes, etc. Can also be used.

(Colorant 3-1: Black colorant)
In a reaction vessel equipped with an ultrasonic generator, a stirrer, a temperature controller, a reflux condenser, and a dropping funnel, 100 parts by weight of ion-exchanged water is put in advance, and the mixture is stirred as a polymerization initiator in a nitrogen atmosphere at 70 ° C. Add 0.2 parts by weight of potassium sulfate. In a separate container, 25 parts by weight of styrene, 20 parts by weight of benzyl methacrylate, 35 parts by weight of n-butyl acrylate, and 5 parts by weight of methacrylic acid were mixed and dissolved to obtain a monomer solution. To this monomer solution, 130 parts by weight of disperse dye disperse black 1 was added and dissolved. Furthermore, 300 parts by weight of ion-exchanged water and 3 parts by weight of a polymerizable surfactant (dispersant having a polymerizable group) Adeka Resorb SE-10N (manufactured by Asahi Denka) are added thereto, and ultrasonic waves are irradiated. While stirring for 30 minutes, an emulsion was obtained. The obtained emulsion was dropped into the reaction vessel, and after completion of the dropping, a polymerization reaction was carried out at the above temperature for 8 hours. The obtained colorant dispersion was neutralized with potassium hydroxide to adjust the pH to around 8, and filtered through a 0.4 μm filter to remove coarse particles. As a result, a target colorant dispersion was obtained. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 120 nm. Moreover, when the glass transition temperature of the coloring agent 3-1 was measured with Seiko Electronics Co., Ltd. product thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200, the glass transition temperature of the polymer of the obtained coloring agent was 13. ° C.

(Colorant 3-2: Cyan colorant)
A target colorant dispersion was obtained in the same manner as (Colorant 3-1) except that Disperse Black 1 was replaced with Disperse Blue 3. Further, the glass transition temperature of the polymer of the colorant 3-2 was 13 ° C.

(Colorant 3-3: Magenta colorant)
A target colorant dispersion was obtained in the same manner as (Colorant 3-1) except that Disperse Black 1 was replaced with Disper Thread 60. The glass transition temperature of the polymer of Colorant 3-3 was 13 ° C.

(Colorant 3-4: Yellow colorant)
A target colorant dispersion was obtained in the same manner as (Colorant 3-1) except that Disperse Black 1 was replaced with Disperse Yellow 3. Further, the glass transition temperature of the polymer of Colorant 3-4 was 13 ° C.

(Colorant 3-5: Black colorant containing film forming aid)
Into a reaction vessel equipped with a dropping device, a thermometer, a water-cooled reflux condenser, and a stirrer, 100 parts by weight of ion-exchanged water is added in advance, and 0.2 wt. Add part. 130 parts by weight of disperse dye 1 15 parts by weight of styrene, 2 parts by weight of glycidyl methacrylate, 16 parts by weight of benzyl methacrylate, 50 parts by weight of n-butyl methacrylate, 15 parts by weight of film forming aid Adecouplernon MPC-709 (manufactured by Asahi Denka Co., Ltd.) And 0.02 part by weight of t-dodecyl mercaptan was dissolved in a monomer solution, and then added to 80 parts by weight of ion-exchanged water to which 0.05 part by weight of sodium lauryl sulfate was added to prepare an emulsion. This was dropped into the reaction vessel maintained at 70 ° C. using a dropping funnel, and adjusted to about pH 8 with potassium hydroxide after completion of the reaction. This was filtered through a 0.4 μm filter to remove coarse particles to obtain a dispersion of the desired colorant. When the glass transition temperature of the colorant was measured by Seiko Electronics Co., Ltd. thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200, the glass transition temperature of the obtained colorant was 25 ° C.

(Colorant 3-6: Cyan colorant)
A target colorant dispersion was obtained in the same manner as (Colorant 3-5) except that Disperse Black 1 was replaced with Disperse Blue 3.

(Colorant 3-7: Magenta colorant)
A target colorant dispersion was obtained in the same manner as in the above (Colorant 3-5) except that Disperse Black 1 was replaced with Disperse Thread 60.

(Colorant 3-8: Yellow colorant)
A target colorant dispersion was obtained in the same manner as (Colorant 3-5) except that Disperse Black 1 was replaced with Disperse Yellow 3.

<Preparation of colorant including pigment in polymer>
(Colorant 4-1: Black pigment: by phase inversion emulsification method)
A colorant containing a pigment in a polymer was produced by the same method as described in JP-A-2000-191972. In a reaction vessel equipped with a stirrer, a temperature controller, a reflux condenser, and a dropping funnel, 20 parts by weight of methyl ethyl ketone, 15 parts by weight of styrene, 12 parts by weight of n-butyl acrylate, 3 parts by weight of 2-hydroxyethyl methacrylate as a polymerization catalyst As a polymerization chain transfer agent, 6 parts by weight of silicone macromer FM-0711 manufactured by Chisso Corporation, 5 parts by weight of styrene-acrylonitrile macromer AN-6 manufactured by Toa Gosei Co., Ltd., 5 parts by weight of dimethylaminoethyl methacrylate 0.6 parts by weight of n-dodecyl mercaptan was charged, and nitrogen substitution was sufficiently performed. On the other hand, in a separate container, 15 parts by weight of styrene, 12 parts by weight of n-butyl acrylate, 3 parts by weight of 2-hydroxyethyl methacrylate, 6 parts by weight of silicone macromer FM-0711 manufactured by Chisso Corporation, Toa Gosei Co., Ltd. 5 parts by weight of styrene-acrylonitrile macromer AN-6 manufactured, 5 parts by weight of dimethylaminoethyl methacrylate, 2.4 parts by weight of n-dodecyl mercaptan as a polymerization chain transfer agent and 60 parts by weight of methyl ethyl ketone, 2,2 as a polymerization initiator A solution prepared by dissolving 0.1 part by weight of '-azobis (2,4-dimethylvaleronitrile) in 5 parts by weight of methyl ethyl ketone was added, reacted at 65 ° C. for 2 hours, and then aged at 70 ° C. for 2 hours to co-polymerize. A combined methyl ethyl ketone solution was obtained. The resulting copolymer had a number average molecular weight of about 10,000 (the molecular weight was measured by gel permeation chromatography). The obtained copolymer solution was dried under reduced pressure to obtain a copolymer. 20 parts by weight of the copolymer solution was dissolved in 100 parts by weight of methyl ethyl ketone, and a 30% gluconic acid aqueous solution was added, so that the salt-forming groups of the copolymer were integrated. Then, 400 parts by weight of ion-exchanged water and 80 parts by weight of carbon black were added and kneaded with a bead mill. The organic solvent was completely removed from the obtained kneaded product at 60 ° C. under reduced pressure, and the coarse particles were removed by filtration through a 0.4 μm filter to obtain a target colorant dispersion. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 120 nm. Further, when the glass transition temperature of the colorant was measured with a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the obtained colorant polymer was 8 ° C. It was.

(Colorant 4-2: Black pigment: According to phase inversion emulsification method)
A colorant containing a pigment in a polymer was produced by the same method as described in JP-A-11-43636. A reactor equipped with a stirrer, temperature controller, reflux condenser, and dropping funnel was charged with 300 parts by weight of methyl ethyl ketone in a flask, and the temperature was raised to 75 ° C. with stirring in a nitrogen atmosphere. 50 parts by weight of styrene, 150 parts by weight of n-butyl methacrylate, 70 parts by weight of butyl acrylate, 35 parts by weight of 2-hydroxyethyl methacrylate, 25 parts by weight of methacrylic acid, and perbutyl O as a polymerization initiator ( Co., Ltd. tert-butyl peroxyoctate) 6.5 parts by weight of the mixed solution was charged into the dropping funnel of the above reaction vessel and dropped over 2 hours. After completion of the dropwise addition, the reaction is further carried out at the same temperature for 15 hours, and the carboxyl group-containing vinyl copolymer having a solid content acid value of 70 KOHmg / g and a number average molecular weight of about 12,500 (the molecular weight is measured by gel permeation chromatography). A combined methyl ethyl ketone solution was obtained. Next, 15 parts by weight of C.I. I. Pigment Blue 15: 3, 15 parts by weight of a methyl ethyl ketone solution of the above-mentioned carboxyl group-containing vinyl copolymer, 0.8 part by weight of dimethylethanolamine and 44.2 parts by weight of ion-exchanged water are primarily mixed and stirred, and then charged into a bead mill. And dispersed. After adding water to the obtained dispersion and diluting it twice, 1N hydrochloric acid was added to the resulting dispersion with stirring with a stirrer to adjust the pH to 3 to 5, thereby insolubilizing the carboxyl group-containing vinyl copolymer. I. Pigment Blue 15: 3 is fixed to C.I., which is included in the carboxyl group-containing vinyl copolymer. I. Pigment Blue 15: 3 dispersion was obtained. This was subjected to suction filtration, washed with water, and C.I. contained in the carboxyl group-containing vinyl copolymer. I. Pigment Blue 15: 3 water-containing cake was obtained. While stirring this water-containing cake with a stirrer, 10% aqueous sodium hydroxide solution was added to adjust the pH to 8.5 to 9.5, and stirring was further continued for 1 hour, and then water was added to obtain a nonvolatile content of 25%. Then, the mixture was further filtered through a 0.4 μm filter to remove coarse particles to obtain a target colorant dispersion. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 100 nm. Further, when the glass transition temperature of the colorant was measured by a thermal scanning calorimeter (differential scanning calorimeter: DSC) DSC200 manufactured by Seiko Electronics Co., Ltd., the glass transition temperature of the obtained colorant polymer was 16 ° C. It was.

<Manufacture of a colorant including a cross-linked structure and an oil-soluble dye>
(Colorant 5-1: Cyan colorant)
Dissolve by adding 100 parts by weight of toluene to 30 parts by weight of the polymer (A) produced in the above (Colorant 2-1), and add 20 parts by weight of oil-soluble dye Vail Fast Blue 2606 (manufactured by Orient Chemical) to disperse the beads. After dispersing using a machine, 1.5 parts by weight of paramentanediamine was further added to the liquid obtained by filtering off the used beads, and mixed and dissolved with a stirrer.
Next, 100 parts by weight of ion-exchanged water was added dropwise to the organic solvent phase and emulsified while stirring and ultrasonic irradiation. This emulsion was subjected to a crosslinking reaction at 80 ° C. for 5 hours after completely removing toluene at 60 ° C. under reduced pressure. Thereafter, the pH was adjusted to around 8 with potassium hydroxide, and the mixture was passed through a 0.4 μm filter to obtain a target colorant dispersion. When the average particle size was measured with a laser Doppler type particle size distribution analyzer Microtrac UPA150 manufactured by Leeds & Northrop, the average particle size was 180 nm. The solid content concentration was 34%.

<Manufacture of a pigment having a polymer group bonded to its surface>
(Colorant 6-1: Black pigment)
A pigment in which a polymer group was bonded to the target surface was obtained by the method described in WO9995169 and JP-A 2000-95987, Example III and Example IV. Details are described below.
A reaction vessel is charged with 11.4 g of sodium nitrite, 28.0 g of sulfanilic acid, and 1200 g of water at 0 ° C. to produce a diazonium salt of sulfanilic acid, in which 200 g of raben C, a carbon black pigment, is added. Was added, and when the generation of nitrogen ceased, the reaction mixture was concentrated and the reaction was further advanced at high temperature. The resulting mixture was Soxhlet extracted with ethanol for 12 hours to remove starting materials and reaction byproducts, dissolved again in water and filtered to obtain about 20 wt% sulfanilic acid treated carbon black pigment dispersion. Next, 3.6 g of aminostyrene, 2.1 g of sodium nitrite, and 150 g of water were charged into another reaction vessel to produce a diazonium salt of 4-aminostyrene, and the diazonium salt produced in 10 g of ethanol was added. Dissolved. Add the sulfanilic acid-treated carbon black pigment dispersion to the above diazonium salt solution, react with stirring for 18 hours, filter, and further purify by Soxhlet extraction and add carbon-pigment with 4-aminostyrene to the surface A dispersion was obtained. Next, after degassing 30 g of deionized water at 90 ° C. in a reaction vessel in a nitrogen atmosphere, a carbon black pigment dispersion with 28.13 g of the above 4-aminostyrene added to the surface of the reaction vessel; A mixture of 2.0 g of methyl methacrylate, 2.0 g of butyl acrylate, and 1.0 g of polyethylene glycol 2000 monomethyl ether acrylate dissolved in 3.0 g of deionized water is added dropwise over 20 minutes. did. To this, 0.22 g of potassium persulfate was added and reacted at 80 ° C. for 18 hours. The obtained product was concentrated under reduced pressure, soxhlet extracted with acetone to remove unadded polymer, and a pigment dispersion having polymer groups bonded to the target surface was obtained.

[Preparation of ink]
Inks having the following compositions (see Tables 1 to 32) were prepared by the following operation. The aqueous medium prepared in advance was gradually added dropwise to the dispersion of the colorant obtained above in the stirring state, and after the dropping was completed, the mixture was sufficiently stirred. This was filtered through a 5 μm membrane filter to obtain an ink.
In Table 1 below, “Real 1” represents the ink of Example 1, “Ratio 1” represents the ink of Comparative Example 1, and the same applies to the other numbers in Table 1 and the numbers in other tables.
The numerical values relating to the ink composition in the following Tables 1 to 32 indicate the content of each constituent with respect to the total amount of ink in weight%. The colorant is added in the form of a dispersion. Therefore, the amount of the dispersion added is calculated from the content of the colorant in the ink and the solid content concentration of the dispersion of the colorant.
Orphine E1010 (manufactured by Nissin Chemical Industry), Olphine STG (manufactured by Nissin Chemical Industry), and Surfynol 465 (manufactured by Air Products) are acetylene glycol surfactants. Surfynol 61 (manufactured by Air Product) is an acetylene alcohol surfactant.
Moreover, the surface tension in the following Tables 1 to 31 is measured with an automatic surface tension meter CBVP-Z type manufactured by Kyowa Interface Science.
The inks of the examples all have ΔSP of 1.0 cal / cm ³ or more.

  Regarding the colorant, the compound represented by the formula (1) and the compound represented by the formula (2), the upper numerical value indicates the content, and the lower mark indicates the colorant, the compound represented by the formula (1) and the formula The kind of compound shown by (2) is shown.

That is, the compounds represented by the above-mentioned titles in the table are as follows.
[1-1]: A compound represented by the formula (1), wherein R is a neopentyl group, n is 1.0, m is 1.5, and M is a hydrogen atom.
[1-2]: A compound represented by the formula (1), wherein R is a t-butyl group, n is 1.0, m is 2.0, and M is a hydrogen atom.
[1-3]: A compound represented by the formula (1), wherein R is 1,3 dimethylbutyl group, n is 0, m is 4.5, and M is a hydrogen atom.
[1-4]: A compound represented by the formula (1), wherein R is an isobutyl group, n is 3.0, m is 1.0, and M is a hydrogen atom.
[1-5]: A compound represented by the formula (1), wherein R is a mixture of 50% n-hexyl group and 50% 2-ethylhexyl group, n of n-hexyl is 4.0, m Is 1.0, n of 2-ethylhexyl is 2.0, m is 1.0, and M is potassium phosphate in both n-hexyl and 2-ethylhexyl.
[1-6]: A compound represented by the formula (1), wherein R is 1,1-dimethylbutyl group, n is 7.0, m is 1.0, and M is sodium borate. is there.
[1-7]: A compound represented by the formula (1), wherein R is a mixture of 50% cyclohexyl group and 50% n-heptyl group, n of the cyclohexyl group is 9.0, and m is 1. 0, M is sodium sulfonate, n of the n-heptyl group is 3.5, m is 2.0, and potassium phosphate.
[1-8]: A compound represented by the formula (1), wherein R is a mixture of 50% neopentyl group, 30% n-pentyl group and 20% isopentyl group. N of the neopentyl group is 0 and m is 1.0, M is K ⁺ , n of the n-pentyl group is 2.5 and m is 1.0, M is ammonium sulfonate, isopentyl The group n is 3.0, m is 1.5, and M is a hydrogen atom.
[1-9]: A compound represented by the formula (1), wherein R is a mixture of 50% cyclohexyl group and 50% n-heptyl group, k of the cyclohexyl group is 9.0, and m is 1.0. M is ammonium borate, k of the n-heptyl group is 3.5 and m is 2.0, and M is triethanolamine borate.
[1-10]: A compound represented by the formula (1), wherein R is a mixture of 50% n-hexyl group and 50% 2-ethylhexyl group, n of n-hexyl is 4.0 and m is 1.0, n of 2-ethylhexyl is 2.0 and m is 1.0. Both n-hexyl and 2-ethylhexyl are triethanolamine sulfonate.
[1-11]: A compound represented by the formula (1), wherein R is a mixture of 50% cyclohexyl group and 50% n-heptyl group, n of the cyclohexyl group is 9.0, and m is 1.0. M is potassium borate, n of the n-heptyl group is 3.5, m is 2.0, and M is ammonium borate.
[1-12]: A compound represented by the formula (1), wherein R is a mixture of 50% neopentyl group, 30% n-pentyl group and 20% isopentyl group. N of the neopentyl group is 0 and m is 1.0, M is K ⁺ , n of the n-pentyl group is 2.5 and m is 1.0, M is ammonium sulfonate, isopentyl The group n is 3.0 and m is 1.5, and M is sodium phosphate.
[1-13]: A compound represented by the formula (1), wherein R is a mixture of 50% n-hexyl group and 50% 2-ethylhexyl group, k of n-hexyl is 4.0 and m is 1.0, k of 2-ethylhexyl is 2.0 and m is 1.0, and both n-hexyl and 2-ethylhexyl are potassium borate.
[1-14]: A compound represented by the formula (1), wherein R is a mixture of 50% n-butyl group and 50% n-heptyl group, and k of the n-butyl group is 9.0. Is 1.0, M is ammonium phosphate, k of the n-heptyl group is 3.5 and m is 2.0, and M is triethanolamine phosphate.
[1-15]: compound represented by formula (1), wherein R is a mixture of 50% cyclohexyl group and 50% n-heptyl group, k of cyclohexyl group is 9.0, and m is 1.0 M is ammonium borate, k of the n-heptyl group is 3.5 and m is 2.0, and M is triethanolamine borate.
[1-16]: A compound represented by the formula (1), wherein R is a neopentyl group, n is 1.0, m is 1.5, and M is sodium.
[1-17]: a compound represented by the formula (1), wherein R is a t-butyl group, n is 1.0, m is 2.0, and M is triethanolamine. .
[1-18]: A compound represented by the formula (1), wherein R is an isobutyl group, n is 3.0, m is 1.0, and M is ammonia.
[1-19]: A compound represented by the formula (1), wherein R is an n-hexyl group, n is 4.0 and m is 1.0, and R is a 2-ethylhexyl group and n is 2 A 1: 1 mixture of 0.0 and m = 1.0, where M is potassium.
[1-20]: A compound represented by the formula (1), wherein R is a mixture of 50% cyclohexyl group and 50% n-heptyl group, n of the cyclohexyl group is 9.0, and m is 1.0. M is a hydrogen atom, n of the n-heptyl group is 3.5, m is 2.0, and M is sodium phosphate.
[1-21]: A compound represented by the formula (1), wherein R is a mixture of 50% neopentyl group, 30% n-pentyl group and 20% isopentyl group. N of the neopentyl group is 0 and m is 1.0, M is K ⁺ , n of the n-pentyl group is 2.5 and m is 1.0, M is ammonium borate, isopentyl group N is 3.0, m is 1.5, and M is a hydrogen atom.
[1-22]: A compound represented by the formula (1), wherein R is a mixture of 50% n-hexyl group and 50% 2-ethylhexyl group, n of n-hexyl is 4.0 and m is 1.0, n of 2-ethylhexyl is 2.0 and m is 1.0, and both n-hexyl and 2-ethylhexyl are potassium sulfonates.
[1-23]: A compound represented by the formula (1), wherein R is a mixture of 50% cyclohexyl group and 50% n-heptyl group, n of the cyclohexyl group is 9.0, and m is 1.0. M is a hydrogen atom, n of the n-heptyl group is 3.5, m is 2.0, and M is sodium phosphate.
[1-24]: A compound represented by the formula (1), wherein R is a mixture of 50% neopentyl group, 30% n-pentyl group and 20% isopentyl group. N of the neopentyl group is 0 and m is 1.0, M is K ⁺ , n of the n-pentyl group is 2.5 and m is 1.0, M is ammonium borate, isopentyl group N is 3.0, m is 1.5, and M is a hydrogen atom.
[1-25]: A compound represented by the formula (1), wherein R is a mixture of 50% cyclohexyl group and 50% n-heptyl group, n of the cyclohexyl group is 9.0, and m is 1.0. Where M is sodium borate, n of the n-heptyl group is 3.5 and m is 2.0, and M is ammonium borate.

[2-1]: A compound represented by the formula (2), wherein n is 2 and EP is ethyleneoxy only.
[2-2]: A compound represented by the formula (2), wherein n is 0.8 and EP is ethyleneoxy only.
[2-3]: A compound represented by the formula (2), wherein n is 4 and EP is a ratio of propyleneoxy 1 to ethyleneoxy3.
[2-4]: A compound represented by the formula (2), wherein n is 1.5 and EP is ethyleneoxy only.
[2-5]: A compound represented by the formula (2), wherein n is 2.8 and EP is ethyleneoxy only.
[2-6]: A compound represented by the formula (2), wherein n is 3.5 and EP is ethyleneoxy only.
[2-7]: A compound represented by the formula (2), wherein n is 10 and EP is ethyleneoxy only.
[2-8]: A compound represented by the formula (2), wherein n is 4.5, and EP is ethyleneoxy only.
[2-9]: A compound represented by the formula (2), wherein n is 4, and EP is ethyleneoxy only.
[2-10]: A compound represented by the formula (2), in which EP is a ratio of ethyleneoxy 3 and propyleneoxy 1 and n is 5.
[2-11]: A compound represented by the formula (2), wherein EP is ethyleneoxy only and n is 3.

  Further, inks of (Comparative Example 3) to (Comparative Example 5) were prepared based on the following compositions.

(Comparative Example 3)
weight(%)
Carbon black pigment (average particle size 105 nm) 5.0
Glycerin 10.0
Dispersant 3.0
Nonionic surfactant 1.0
Remaining amount of ion-exchanged water Carbon black pigment: Raven C (manufactured by Columbia Carbon Co., Ltd.)
Nonionic surfactant: Neugen EA160 (Daiichi Kogyo Seiyaku Co., Ltd.)
Dispersant: Jonkrill 62 (manufactured by Johnson Polymer)

(Comparative Example 4)
weight(%)
Acid Blue 9 5.5
DEGmME 7.0
Diethylene glycol 10.0
2-pyrrolidone 5.0
Ion exchange water

(Comparative Example 5)
weight(%)
Direct Black 154 2.5
Diethylene glycol 10.0
Nonionic surfactant 1.0
Remaining amount of ion-exchanged water Nonionic surfactant: Epan 450 (Daiichi Kogyo Seiyaku Co., Ltd.)

  Further, in the composition of Comparative Example 3, at least one compound selected from the group of acetylene glycol surfactants, acetylene alcohol surfactants, glycol ethers and 1,2-alkylene glycols is shown in Table 32 below. Thus, the inks of Comparative Examples 6 to 15 were prepared by further addition.

The following evaluation tests were performed on the inks of the above examples and comparative examples.
<Evaluation 1: Print quality>
For each ink, 24 uppercase and lowercase letters of the alphabet were printed on the following papers using an inkjet printer MJ-930C (manufactured by Seiko Epson Corporation), visually observed, and evaluated according to the following criteria.
SA: There is no bleeding on all paper and the printing density is high.
AA: Although no bleeding occurs on all sheets, the print density is lower than that of the SA rank.
A: Only slight occurrence of bleeding is observed on 2-3 sheets.
B: Slight bleeding is observed on all papers.
C: There is much bleeding on the entire paper.
The paper used for the evaluation is Conqueror paper, Favorit paper, Modo paper, Rapid Copy paper, Epson EPP paper, Xerox P paper, Xerox 4024 paper, Xerox 10 paper, Nenha Bond paper, Rcopy 6200 paper, and Yamari paper (recycled paper) Xerox R paper (recycled paper).

<Evaluation 2: Water resistance>
1 ml of ion-exchanged water was dropped on the printed portion of the printed matter obtained in the print quality test of Evaluation 1, and the state after 20 minutes was visually observed and evaluated according to the following criteria.
A: There is no change in the whole paper.
B: Although the color material slightly flows out from the print portion, the character can be recognized.
C: It is difficult to recognize the character because the color material flows out from the printed portion and the outline of the printed character is unclear.

<Evaluation 3: Dispersion stability (1)>
Each ink was sealed in a glass sample bottle (50 ml), allowed to stand at 60 ° C. for 2 weeks, and the viscosity of the ink before and after being left was measured. The measurement was performed under the conditions of 20 ° C. and 150 S ⁻¹ using Rheometrics Scientific RFS2. The obtained results were evaluated according to the following criteria.
SA: Change amount is less than ± 0.02 mPa · s AA: Change amount is ± 0.02 or more and less than 0.05 mPa · s A: Change amount is ± 0.05 or more and less than 0.1 mPa · s B: Change amount is ± 0.1 or more and less than 0.3 mPa · s C: Change amount is ± 0.3 mPa · s or more.

<Evaluation 4: Dispersion stability (2)>
Each ink was sealed in a glass sample bottle (50 ml) and allowed to stand at 60 ° C. for 2 weeks. The presence or absence of precipitates and foreign matters was examined and evaluated according to the following criteria.
A: No sediment or foreign matter is generated.
B: Precipitation and foreign matter are generated.

<Evaluation 5: Clogging reliability (1)>
Each ink is filled into the head of an ink jet printer MJ-930C manufactured by Seiko Epson, and alphanumeric characters are printed continuously for 10 minutes. Thereafter, the printer was stopped and left for 2 weeks in an environment of 40 ° C. and humidity of 25% without capping. Alphanumeric characters were printed again after being left, and the number of times required to obtain the same print quality as before being left (number of return operations) was evaluated and evaluated according to the following criteria.
SA: Print quality equivalent to that before standing was obtained after 0 to 1 return operation.
AA: A printing quality equivalent to that before standing was obtained after 2 to 3 returning operations.
A: Print quality equivalent to that before standing was obtained after 3-4 returning operations.
B: Print quality equivalent to that before standing was obtained after 5 to 6 returning operations.
C: Print quality equivalent to that before standing could not be obtained even after 7 return operations.

<Evaluation 6: Discharge stability>
For each ink, alphanumeric characters were continuously printed on Xerox P paper using an inkjet printer MJ-930C (manufactured by Seiko Epson Corporation), and the printing state such as missing dots and ink landing position deviation was visually observed. The evaluation was based on the following criteria.
SA: No dot missing or ink landing position deviation even when printing 50000 sheets or more.
AA: When the number of printed sheets is 10,000 or more and less than 50000, dot missing or ink landing deviation occurs.
A: When the number of printed sheets is 1000 or more and less than 10,000, dot missing or ink landing deviation occurs.
B: Omission of dots or ink landing deviation occurs at 100 or more and less than 1000.
C: When less than 100 sheets, dot missing or ink landing deviation occurs.

<Evaluation 7: Abrasion resistance>
Each ink was solid-printed at 100% duty on a 10 mm × 10 mm area on a Seiko Epson superfine glossy film using the head of an ink jet printer MJ-930C manufactured by Seiko Epson, and left at a temperature of 25 ° C. for 1 hour. The above printed area was rubbed at a speed of 10 mm / sec with a load of 500 g using a yellow aqueous fluorescent pen ZEBRA PEN2 (trademark) manufactured by Zebra Corporation, and the presence or absence of stains was observed. The results were evaluated according to the following criteria.
A: Dirt does not occur at all even after rubbing twice.
B: Dirt is not generated by rubbing once, but dirt is generated by rubbing the second time.
C: Dirt is generated by rubbing once.

<Evaluation 8: Quick-drying>
For each ink, use a inkjet printer MJ-930C (manufactured by Seiko Epson Corporation) to print a solid 10% × 10 mm area on Xerox P paper with 100% duty 10 seconds later. Then, a 300 g weight was placed and removed after leaving for 10 seconds, and it was confirmed whether ink was attached to the latter paper. The results were evaluated according to the following criteria.
A: No ink adhesion B: Ink adhesion

As described above, the inks of the examples were able to obtain high-quality images with reduced blur on printed images when printed on various plain papers and recycled papers (Yamayuri, Xerox®).
On the other hand, when using an ink in which a pigment is dispersed with a general dispersant (Comparative Example 3) or an ink using a dye as a colorant (Comparative Examples 4 and 5), bleeding occurs, resulting in high quality. Could not get the image.
Since the colorants of the inks of the examples are insoluble in water, compared to the case where a water-soluble dye is used as in Comparative Examples 4 and 5, the image is markedly superior in terms of water resistance.

As described above, as can be seen from the results of Tables 32 to 49, the inks of Examples exhibited good dispersion stability and ejection stability with almost no precipitate or foreign matter and no change in physical property values.
That is, it was selected from the group consisting of “colorant including pigment and / or dye in polymer” and “acetylene glycol surfactant, acetylene alcohol surfactant, glycol ethers and 1,2-alkylene glycol”. It was confirmed for the first time that good ejection stability and dispersion stability were obtained by combining with one or more compounds.

  On the other hand, an ink in which a pigment is dispersed by an ordinary dispersant is added with a “colorant containing a pigment and / or a dye as a polymer”, “acetylene glycol surfactant, acetylene alcohol surfactant, glycol ethers and Even when one or more compounds selected from the group consisting of 1,2-alkylene glycol were added (Comparative Examples 6 to 15), good dispersion stability and ejection stability could not be obtained.

Further, the ink further containing one or more compounds selected from the group consisting of polyhydric alcohol and the compound represented by the above formula (1) has no generation of precipitates or foreign matters, and there is no change in physical property values. Good dispersion stability and ejection stability were exhibited.
In addition, the ink further containing sugar and one or more compounds selected from the group represented by the formula (2) and glycerin exhibited extremely good clogging reliability.
Furthermore, when the surface tension exceeded 45 mN / m, quick drying was inferior and bleeding was likely to occur. Further, when it was less than 25 mN / m, ejection was unstable. That is, it was confirmed that the surface tension of the ink is preferably in the range of 25 to 45 mN / m.

<Evaluation test: Clogging reliability (2)>
With respect to the “colorant including the pigment in the polymer” contained in the inks of Examples 127 to 134, the weight percentage of the “polymer” with respect to the “colorant including the pigment in the polymer” (hereinafter also referred to as “polymer amount”). ) Was changed as shown in Table 50, and a clogging reliability test was conducted. In other words, the clogging reliability test was performed when an ink jet printer MJ-930C manufactured by Seiko Epson Corporation was used, and each ink was put in a cartridge and taken out in an environment of 40 ° C. and 20% humidity for 3 months. This was performed by a method of measuring the number of times of recovery in the cleaning mode (a mode for recovering when missing dots etc. provided in the ink jet printer MJ-930C manufactured by Seiko Epson Corporation). The recovery after 3 times or less was A, the recovery at 4 to 5 times was B, the recovery at 5 to 20 times was C, and the recovery at 20 or more times was D.

  As can be seen from the results in Table 50, it was confirmed that the clogging recovery property was particularly good when the polymer amount was 10% by weight or more.

  In addition, regarding the “colorant including the pigment in the polymer” included in the color inks of Examples 128 to 134, the amount of the colorant polymer was changed as shown in Table 51, and MOH930C was used to make the OHP paper (Seiko Epson). The measurement results of the turbidity value when solid printing is made on The turbidity was measured using a haze meter (manufactured by Suga Test Instruments Co., Ltd.). Smaller values indicate less turbidity and transparency.

  As can be seen from the results in Table 51, it was confirmed that the transparency of the color with respect to a transparent sheet such as OHP was particularly good when the polymer amount was 10% by weight or more.

<Evaluation test: abrasion resistance>
In the production of the “colorant including a pigment in the polymer” contained in the ink of Example 1, the total weight part of styrene and butyl acrylate was maintained at 60 parts by weight, and the weight ratio of styrene and butyl acrylate was Tables 52 and 53 show the evaluation results of the abrasion resistance when the glass transition temperature and the film formation temperature of the polymer were changed to be changed to the ratios shown in 52 and Table 53, respectively.
The film formation temperature described is that the ink is printed at a predetermined temperature using a Seiko Epson inkjet printer MJ-930C head on a 10 mm x 10 mm area of 100% duty on a Seiko Epson Superfine glossy film. After leaving at the same temperature for 1 hour, the above printed area was rubbed at a speed of 10 mm / second under a load of 500 g using a yellow aqueous fluorescent pen ZEBRA PEN2 (trademark) manufactured by Zebra Co. Evaluation of abrasion resistance was performed by the method described in Evaluation 7 above.

As can be seen from Table 52 and Table 53, it was confirmed that the abrasion resistance was particularly improved when the glass transition temperature and the film formation temperature of the polymer portion of the colorant were 25 ° C. or lower.
In the preparation of “colorant including pigment in polymer” contained in the inks of Examples 2 to 4 and 31 to 34, the weight ratio of styrene and butyl acrylate is changed as shown in Table 52 and Table 53 above. The same test was performed, and the results were almost the same as those in Table 52 and Table 53, respectively (in the method for producing a colorant including a pigment or a dye in a polymer, the total weight part of styrene and butyl acrylate). Is 60 parts by weight for Examples 2-4 and 65 parts by weight for Examples 31-34).

  Table 54 and Table 55 show the amounts of the film forming aid Adecouplernon MCP-709 added to the ink, which is a poorly water-soluble substance, in the production of the “colorant including a pigment in the polymer” included in the ink of Example 190. Tables 54 and 55 show the evaluation results of the abrasion resistance when the values are changed to the values shown.

As can be seen from Table 54 and Table 55, it was confirmed that the abrasion resistance was particularly improved when the glass transition temperature and the film formation temperature of the polymer portion of the colorant were 25 ° C. or lower.
In the production of the “colorant including a pigment in the polymer” included in the inks of Examples 191 to 197, the same was achieved by changing the content of the film forming auxiliary as shown in Table 54 and Table 55 above. The results were almost the same as in Table 54 and Table 55, respectively.

<Evaluation test: Storage stability>
The storage stability and ejection stability were evaluated using the inks of Examples 198 to 205, the ink from which the preservative was removed, the ink from which the metal ion scavenger was removed, and the ink from which the rust inhibitor was removed. The results are shown in Table 56.
The storage stability was examined for the occurrence of odor and mold when a cartridge of an ink jet printer MJ-930C manufactured by Seiko Epson Corporation was filled with ink and left at 30 ° C. for half a year. The case where no foreign matter was confirmed by visual observation was A, and the case where a very small amount of foreign matter was confirmed was designated B. Moreover, the case where generation | occurrence | production of off-flavor and mold was not recognized was set to A, and the case where generation | occurrence | production of off-flavor and mold was recognized was set to B. Furthermore, the case where rust generation was not observed at the nozzle portion of the ink jet printer was designated as A, and the case where rust occurrence was observed was designated as B.

  As can be seen from Table 56, the ink contains a preservative, a metal ion scavenger, and ethylenediamine acetate, and the preservative is an alkyl isothiazolone, chloroalkyl isothiazolone, benzisothiazolone, bromonitroalcohol, oxazolidine compound. And one or more compounds selected from the group consisting of chloroxylenol, and the metal ion scavenger is ethylenediamineacetate and the rust inhibitor is dicyclohexylammonium nitrate and / or benzotriazole, especially for storage It was confirmed that the stability was improved.

As described above, according to the present invention, a high-quality image having excellent dispersion stability and ejection stability, no bleeding on plain paper and recycled paper, high printing density, and excellent color development. Ink jet recording ink and recording method can be provided.
Further, according to the present invention, it is possible to provide an ink for ink jet recording and a recording method capable of obtaining sufficient abrasion resistance not only on plain paper and recycled paper but also on recording media such as coated paper.

Further, according to the present invention, it is possible to provide an ink for inkjet recording excellent in long-term storage stability.
Further, according to the present invention, it is possible to provide a recorded matter having a high-quality image having a high printing density and excellent color developability and having sufficient abrasion resistance.
Furthermore, according to the present invention, it is possible to provide an ink jet recording apparatus that has a high-quality image having a high printing density and excellent color developability, and can obtain a recorded matter having sufficient abrasion resistance.

Claims (54)

  One or more selected from the group consisting of a acetylene glycol-based surfactant and an acetylene alcohol-based surfactant, and containing a colorant and water containing a pigment and / or dye as a polymer by a phase inversion emulsification method And an 1,2- (C4-C10 alkyl) diol compound, wherein the surface tension is in the range of 25 mN / m to 45 mN / m. Recording ink.   In addition to one or more compounds selected from the group consisting of the acetylene glycol surfactants and acetylene alcohol surfactants, and 1,2- (alkyl having 4 to 10 carbon atoms) diols, glycols are also included. The ink for ink jet recording according to claim 1, comprising an ether compound.   The content of one or more compounds selected from the group consisting of the acetylene glycol surfactants and acetylene alcohol surfactants, and 1,2- (C4-10 alkyl) diol compounds, or The ink for inkjet recording according to claim 1 or 2, wherein the content of the glycol ether compound is 0.5 to 30% by weight.   4. One or more compounds selected from the group consisting of the acetylene glycol surfactant and the acetylene alcohol surfactant are contained in an amount of 0.5 to 5% by weight. 5. The ink for inkjet recording as described.   Contains 0.5 to 5% by weight of one or more compounds selected from the group consisting of the acetylene glycol surfactants and acetylene alcohol surfactants, and 1,2- (alkyl having 4 to 10 carbon atoms) 5) A diol compound, or a 1,2- (alkyl having 4 to 10 carbon atoms) diol compound and a glycol ether compound are contained in an amount of 1% by weight or more. The ink for inkjet recording as described.   One or more compounds selected from the group consisting of the acetylene glycol surfactants and acetylene alcohol surfactants are 2,4-dimethyl-5-hexyn-3-ol, 2,4,7,9- Tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, and the 2,4-dimethyl-5-hexyn-3-ol, 2,4 , 7,9-tetramethyl-5-decyne-4,7-diol and 3,6-dimethyl-4-octyne-3,6-diol, respectively, have an average of ethyleneoxy group and / or propyleneoxy group The ink for inkjet recording according to any one of claims 1 to 5, wherein the ink is one or more compounds selected from the group consisting of:   The glycol ethers are diethylene glycol mono (C 1-8 alkyl) ether, triethylene glycol mono (C 1-8 alkyl) ether, propylene glycol mono (C 1-6 alkyl) ether, dipropylene The ink for inkjet recording according to any one of claims 2 to 6, which is one or a mixture of two or more selected from the group consisting of glycol mono (C1-6 alkyl) ethers.   The ink for inkjet recording according to any one of claims 2 to 6, wherein the glycol ether is di (tri) ethylene glycol monobutyl ether and / or (di) propylene glycol monobutyl ether.   9. The ink for ink jet recording according to claim 8, comprising 10% by weight or less of (di) propylene glycol monobutyl ether.   The weight of the compound and (di) propylene glycol monobutyl ether is 0.5% by weight or more of one or more compounds selected from the group consisting of the acetylene glycol surfactant and the acetylene alcohol surfactant. The ink for inkjet recording according to claim 8 or 9, wherein the ratio is 1: 0 to 1:10.   The ink for inkjet recording according to any one of claims 8 to 10, comprising 20% by weight or less of the di (tri) ethylene glycol monobutyl ether.   Containing at least 0.5% by weight of one or more compounds selected from the group consisting of the acetylene glycol surfactants and acetylene alcohol surfactants, and the compound and di (tri) ethylene glycol monobutyl ether The ink for inkjet recording according to any one of claims 8 to 11, wherein the weight ratio is 1: 0 to 1:10.   The inkjet according to claim 1, wherein the 1,2- (alkyl having 4 to 10 carbon atoms) diol is 1,2-pentanediol and / or 1,2-hexanediol. Recording ink.   The ink for inkjet recording according to any one of claims 1 to 13, comprising a compound of 1,2- (alkyl having 4 to 10 carbon atoms) diol in an amount of 15 wt% or less. The ink for inkjet recording according to any one of claims 1 to 14, further comprising at least one compound selected from the group consisting of a polyhydric alcohol and a compound represented by the following formula (1). Ink for inkjet recording.
Formula (1) R-EOn-POm-M
R is an alkanol group having 4 to 12 carbon atoms, a cycloalkanol group, a phenol group, and / or a naphthol group, and is a straight chain and / or other isomer. EO represents an ethyleneoxy group, PO represents a propyleneoxy group, n and m are repeating units, and represent an average value in the entire system. EO and PO are present in the molecule and the order is not relevant. M is a hydrogen atom, a sulfonate group, a phosphate group and / or a borate group, and the counter ion of the sulfonate group, phosphate group and / or borate group is hydrogen, an alkali metal, an inorganic base and / or an organic amine.   The ink for inkjet recording according to claim 15, wherein n in the formula (1) is 0 to 10, and m is 1 to 5.   The ink for inkjet recording according to claim 15 or 16, wherein the compound represented by the formula (1) has an average molecular weight of 2000 or less.   The content of the acetylene glycol surfactant is 5% by weight or less, and the ratio of the compound represented by the formula (1) to the acetylene glycol surfactant is 1: 0 to 1: 3. The ink for inkjet recording in any one of Claims 15-17.   The glycol ether is (di) propylene glycol butyl ether monobutyl ether, contains the glycol ether in an amount of 10% by weight or less, and the weight ratio of the compound represented by the formula (1) to the glycol ether is 1: The ink for inkjet recording according to any one of claims 15 to 18, wherein the ink is 0 to 1:10.   The glycol ether is di (tri) ethylene glycol monobutyl ether, the glycol ether is contained in an amount of 20% by weight or less, and the weight ratio of the compound represented by the formula (1) to the glycol ether is 1: The ink for inkjet recording according to any one of claims 15 to 18, wherein the ink is 0 to 1:10.   The weight ratio of the compound represented by the formula (1) and the 1,2- (alkyl having 4 to 10 carbon atoms) diol is 1: 0 to 1:10, The ink for inkjet recording in any one of 20.   The ink for inkjet recording according to any one of claims 15 to 21, wherein the polyhydric alcohol is an alkyl diol having 3 to 12 carbon atoms and / or an alkyl triol having 3 to 12 carbon atoms.   The ink for ink-jet recording according to any one of claims 1 to 22, further comprising glycerin.   24. The ink for ink jet recording according to claim 23, further comprising sugar. The ink for inkjet recording according to any one of claims 1 to 24, further comprising a compound represented by the following formula (2).
Formula (2) A- (EP) n
A represents a glycerin skeleton, and EP represents an ethyleneoxy group (terminal OH) and / or a propyleneoxy group (terminal OH), but may be an OH group. N is a repeat unit.   26. The ink for inkjet recording according to claim 25, wherein n in the formula (2) is 0.5 to 10.   27. The ink for ink jet recording according to claim 25 or 26, wherein the compound represented by the formula (2) has an average molecular weight of 1000 or less.   The ink for inkjet recording according to any one of claims 24 to 27, wherein 80% by weight or more of the sugar is aldose, ketose and / or sugar alcohol having 12 or less carbon atoms.   The ink for inkjet recording according to any one of claims 1 to 28, wherein the dye is a dye insoluble or hardly soluble in water.   The inkjet according to any one of claims 1 to 29, wherein an addition amount of a colorant including the pigment and / or dye as a polymer by a phase inversion emulsification method is 0.5 wt% to 30 wt%. Recording ink.   The colorant is a colorant containing a pigment and / or dye in a polymer by a phase inversion emulsification method, and the content of the polymer is 10% by weight or more based on the total amount of the colorant. The ink for inkjet recording according to any one of claims 1 to 30.   The polymer including a pigment and / or a dye is mainly composed of one or more selected from the group consisting of vinyl polymers, polyesters, polyamides, polyimides, silicon-containing polymers and sulfur-containing polymers. The ink for inkjet recording in any one of 1-3.   The ink for inkjet recording according to any one of claims 1 to 31, wherein the polymer including a pigment and / or a dye is a polymer having a crosslinked structure.   The colorant including the pigment and / or the dye with a polymer having a crosslinked structure makes a phase-inversion emulsification by bringing an organic phase containing at least a polymer having a crosslinking reactive group and a hydrophilic group and a crosslinking agent into contact with an aqueous phase. The ink jet recording according to claim 33, wherein the ink jet recording is obtained by including a pigment and / or a dye in the polymer and then performing a crosslinking reaction between the polymer and a crosslinking agent. For ink.   The polymer having a crosslinking reactive group and a hydrophilic group is a vinyl polymer, poly (meth) acrylic acid ester, styrene- (meth) acrylic acid copolymer, polyester, polyamide, polyimide, polyurethane, amino-based polymer. 35. The ink jet recording according to claim 33 or claim 34, comprising at least one selected from the group consisting of a polymer, a silicon-containing polymer, a sulfur-containing polymer, a fluorine-containing polymer and an epoxy resin as a main component. For ink.   The hydrophilic group of the polymer having the crosslinking reactive group and the hydrophilic group is selected from the group consisting of a sulfone group, a sulfonic acid group, a carboxyl group, a hydroxyl group, and a salt thereof and a quaternary ammonium salt. 36. The ink for inkjet recording according to any one of claims 33 to 35.   34. The cross-linking reactive group of the polymer having the cross-linking reactive group and the hydrophilic group is selected from the group consisting of a glycidyl group, an isocyanate group, a hydroxyl group, and an unsaturated hydrocarbon group. 36. The ink for inkjet recording according to any one of 36.   The ink for inkjet recording according to claim 37, wherein the unsaturated hydrocarbon group is selected from the group consisting of a vinyl group, an allyl group, an acryloyl group, a methacryloyl group, a propenyl group, a vinylidene group, and a vinylene group. .   The cross-linking agent has at least two functional groups capable of reacting with the cross-linking reactive group of the polymerization having the cross-linking reactive group and the hydrophilic group in the molecule. The ink for inkjet recording according to any one of 38.   The functional group of the crosslinking agent is selected from the group consisting of amino group, carboxyl group, hydroxyl group, carboxyl group, mercapto group, glycidyl group, isocyanate group, N-methylol group, N-methylol ether group, unsaturated hydrocarbon group. 40. The ink for inkjet recording according to any one of claims 34 to 39, wherein:   The ink for inkjet recording according to claim 40, wherein the unsaturated hydrocarbon group is selected from the group consisting of a vinyl group, an allyl group, an acryloyl group, a methacryloyl group, a propenyl group, a vinylidene group, and a vinylene group. .   The said crosslinking agent is 0.01-0.1 by weight ratio with respect to the polymer which has the said crosslinking reactive group and a hydrophilic group, The any one of Claims 34-41 characterized by the above-mentioned. Ink for ink jet recording.   43. The ink for inkjet recording according to claim 34, wherein a reactive surfactant is contained in the organic phase. The solubility parameter of the polymer including pigments and / or dyes is in the range of 11 to 14 cal / cm ³ , and the difference between the solubility parameter of the liquid component and the solubility parameter of the polymer is 1.0 cal / cm The ink for inkjet recording according to any one of claims 1 to 43, wherein the ink is ³ or more.   45. The ink for ink jet recording according to any one of claims 1 to 44, wherein an acid value of the polymer including a pigment and / or a dye is 20 to 200 KOHmg / g.   The ink for inkjet recording according to any one of claims 1 to 45, wherein a glass transition temperature of the polymer including a pigment and / or a dye is 25 ° C or lower.   The ink for inkjet recording according to any one of claims 1 to 46, wherein a film forming temperature of the polymer including a pigment and / or a dye is 25 ° C or lower.   The ink for inkjet recording according to any one of claims 1 to 47, wherein a poorly water-soluble substance is contained in a colorant including a pigment and / or a dye in the polymer.   49. The ink for inkjet recording according to claim 48, wherein the solubility of the hardly water-soluble substance in water is 10% by weight or less.   The ink for inkjet recording according to any one of claims 1 to 49, comprising a preservative, a metal ion scavenger, and a rust preventive, wherein the preservative is an alkyl isothiazolone, chloroalkyl isothiazolone, benzisothiazolone, bromonitro alcohol. One or more compounds selected from the group consisting of oxazolidine compounds and chlorxylenol, the metal ion scavenger is ethylenediamine acetate, and the rust inhibitor is dicyclohexylammonium nitrate and / or benzotriazole Ink for ink jet recording characterized by the above-mentioned.   The addition amount (A) of the preservative is 0.01 wt% to 0.1 wt%, the addition amount (B) of the metal ion scavenger is 0.01 wt% to 0.5 wt%, The addition amount (C) of the rust inhibitor is 0.01 wt% to 0.2 wt%, and A + B + C is 0.03 wt% to 0.8 wt%. Ink jet recording ink.   52. A recording method for performing printing by discharging ink droplets and attaching the droplets to a recording medium, wherein the ink for ink jet recording according to any one of claims 1 to 51 is used. Recording method.   53. A recorded matter printed by the recording method according to claim 52.   An electrostrictive element that can vibrate based on an electric signal is mounted, and the ink jet recording ink according to any one of claims 1 to 51 can be ejected by vibration of the electrostrictive element. An ink jet recording apparatus.