JP5217088B2 - Inkjet ink, inkjet ink set, and inkjet recording method - Google Patents

Description

  The present invention relates to an inkjet ink and an ink set having improved water resistance without causing beading or color bleeding on a recording medium having little ink absorption or no ink absorption, and a recording method. is there.

  The ink jet recording method is capable of recording high-definition images with a relatively simple apparatus, and has been rapidly developed in various fields. In addition, there are various uses, and a recording medium or ink suitable for each purpose is used.

  In particular, in recent years, the recording speed has been greatly improved, and printers having performance capable of withstanding light printing applications have been developed.

  However, in order to bring out the performance of the ink jet printer, an ink jet dedicated paper provided with ink absorbability is required as a recording medium.

  When recording on coated paper or art paper that does not absorb much ink, or on plastic film that does not absorb ink at all, different color inks mix on the recording medium and cause color turbidity. Therefore, there has been a problem in providing a variety of recording media for the ink jet recording method.

  In the above problems, a hot-melt ink composition made of a wax that is solid at room temperature is used, liquefied by heating, etc., sprayed with some energy applied, cooled and solidified while adhering to the recording medium, and recorded A hot-melt ink jet recording method for forming dots has been proposed.

  Since this ink is solid at room temperature, it does not get dirty during handling, and since there is substantially no ink evaporation during melting, there is no clogging of the nozzles. Furthermore, an ink composition has been proposed that solidifies immediately after adhering and has less color bleeding and provides good print quality regardless of paper quality (see Patent Documents 1 and 2).

  However, an image recorded by such a method has problems such as deterioration of quality due to the rising of the dots and lack of scratching performance because the ink dots are in the form of soft wax.

  On the other hand, an inkjet recording ink that is cured by irradiation with ultraviolet rays is disclosed (see Patent Document 3). In addition, a so-called non-aqueous ink containing a pigment and a triacrylate or higher polyacrylate as a polymerizable material and using a ketone or alcohol as a main solvent has been proposed (see Patent Document 4). An ink using an aqueous ultraviolet polymerization monomer has been proposed (see Patent Document 5).

  According to these methods, since the ink itself is cured with a curing component, recording is possible even on a non-absorbing recording medium, but a large amount of a curing component other than a coloring material is contained and does not volatilize. The recording surface was swelled by ink dots, causing unnaturalness in image quality, particularly glossiness.

Furthermore, there are environmental safety concerns regarding conventionally known curing components, and even if safety is cleared, the range for selecting the material to be used is narrow, and it is impossible to design materials and physical properties freely. There was a problem.
US Pat. No. 4,391,369 U.S. Pat. No. 4,484,948 U.S. Pat. No. 4,228,438 Japanese Patent Publication No. 5-64667 JP-A-7-224241

  The present inventors can solve the above problems by adopting an ink containing a polymer compound having a plurality of side chains in a hydrophilic main chain and capable of crosslinking between side chains by irradiating active energy rays. I found what I can do.

  However, it has also been found that when this method is employed, water resistance is insufficient depending on the image.

  Accordingly, an object of the present invention is to provide an ink-jet ink set and an ink-jet ink set with improved water resistance, which do not cause beading or color bleeding on a medium with little ink absorbability or non-ink absorbability, and An inkjet recording method is provided.

  The above problem could be solved by the following configuration.

1. In an inkjet ink containing at least a coloring material, water, and a polymer compound having a side chain that is crosslinked by irradiating an active energy ray to a hydrophilic main chain, and capable of crosslinking between the side chains,
An ink-jet ink, wherein the hydrophilic main chain is silanol-modified polyvinyl alcohol .

2 . 2. The inkjet ink according to 1, wherein the polymer compound is contained in an amount of 0.8 to 5.0% by mass based on the total mass of the ink.

3 . 3. The inkjet ink according to 1 or 2 , wherein the hydrophilic main chain has a saponification degree of 77 to 99% and a polymerization degree of 200 to 4000.

4 . The inkjet ink according to any one of claims 1 to 3 , wherein a modification rate of the side chain with respect to the hydrophilic main chain is 0.8 mol% or more and 4 mol% or less.

5 . The inkjet ink according to any one of 1 to 4 , further comprising a water-soluble photopolymerization initiator.

6 . An ink jet ink set comprising two or more ink jet inks, wherein at least one of the ink jet inks is the ink jet ink according to any one of 1 to 5 .

7 . An ink jet recording method comprising: discharging the ink jet ink according to any one of 1 to 5 onto a recording medium, irradiating with an active energy ray, and drying.

8 . An ink jet recording method comprising: discharging ink jet ink of the ink jet ink set according to 6 onto a recording medium, irradiating with active energy rays, and drying.

  According to the present invention, an ink-jet ink and an ink-jet ink set having improved water resistance and an ink-jet recording method having no ink absorption or no beading or color bleeding on a medium having no ink absorption are provided. Could be provided.

  Hereinafter, the present invention will be described in detail.

  In the present invention, the hydrophilic main chain is silanol-modified PVA, and has a side chain that is cross-linked by irradiating active energy rays, and a polymer compound that can be cross-linked between the side chains is contained in the ink. Thus, after printing, the ink itself thickens on the recording medium, and the occurrence of color mixing between different colors (color bleed) and mottle (beading) due to ink overflow can be suppressed. Therefore, it is possible to print directly on a recording medium having no absorbency.

  Conventionally, there has been a technique of putting a component that cures with active energy in this way into the ink. However, the component to be cured is a monomer, energy efficiency is low, and if a considerable amount is not added to the ink, it is non-absorbing It was not possible to print directly on the recording medium. For this reason, the swell of the image portion is increased, and an image having a high smoothness cannot be obtained.

  In the present invention, since a small amount of the curing component is sufficient and the total solid content in the ink can be suppressed to about 10%, the rise of the image area after the volatile component is volatilized is very small. Therefore, it is possible to print an image with high image quality and high smoothness as it is on a recording medium having low or no absorbency such as printing paper.

  Further, since the hydrophilic main chain is silanol-modified PVA, the swelling property of the polymer compound with respect to water is suppressed, and the water resistance of the printed image is improved.

<Active energy ray crosslinkable polymer compound>
The hydrophilic main chain according to the present invention is silanol-modified PVA, the main chain has a plurality of side chains, and a polymer compound that can be cross-linked between side chains by irradiating active energy rays is silanol. A modified group such as a photodimerization type, a photodecomposition type, a photopolymerization type, a photomodification type, and a photodepolymerization type is introduced into the side chain of the modified PVA. Photopolymerizable crosslinkable groups are desirable from the viewpoints of sensitivity and performance of the generated image.

  In the hydrophilic main chain, a saponified product of polyvinyl acetate is preferable from the viewpoint of ease of introduction of side chains and handling, and the polymerization degree is preferably 200 or more and 4000 or less, and 200 or more and 2000 or less is more preferable from the viewpoint of handling. preferable. The modification rate of the side chain with respect to the main chain is preferably 0.3 mol% or more and 4 mol% or less, and more preferably 0.8 mol% or more and 4 mol% or less from the viewpoint of reactivity. If it is less than 0.3 mol%, the crosslinkability is insufficient and the effect of the present invention is reduced. If it is more than 4 mol%, the crosslink density is increased and the film is hard and brittle, and the strength of the film is lowered.

  As the photodimerization-type modifying group, those in which a diazo group, a cinnamoyl group, a stilbazonium group, a stilquinolium group or the like is introduced are preferable. For example, a photosensitive resin described in JP-A-60-129742 (Composition).

  The photosensitive resin described in JP-A-60-129742 is a compound represented by the following general formula (1) in which a stilbazonium group is introduced into a polyvinyl alcohol structure.

In the formula, R ₁ represents an alkyl group having 1 to 4 carbon atoms, and A ⁻ represents a counter anion.

  The photosensitive resin described in JP-A-56-67309 includes a 2-azido-5-nitrophenylcarbonyloxyethylene structure represented by the following general formula (2) in the polyvinyl alcohol structure, or the following general formula. A resin composition represented by (3) and having a 4-azido-3-nitrophenylcarbonyloxyethylene structure is also preferred.

  Further, a modifying group represented by the following general formula (4) is also preferably used.

  In the formula, R represents an alkylene group or an aromatic ring. A benzene ring is preferred.

  As the photopolymerization type modifying group, for example, a resin represented by the following general formula (5) shown in JP-A Nos. 2000-181062 and 2004-189841 is preferable from the viewpoint of reactivity.

In the formula, R ₂ represents a methyl group or a hydrogen atom, n represents 1 or 2, X represents — (CH ₂ ) _m —COO— or —O—, and Y represents an aromatic ring or a single bond. And m represents an integer from 0 to 6.

  Moreover, it is also preferable to use the photopolymerization type | mold modified group represented by following General formula (6) described in Unexamined-Japanese-Patent No. 2004-161942 for a conventionally well-known water-soluble resin.

In the formula, R ₃ represents a methyl group or a hydrogen atom, and R ₄ represents a linear or branched alkylene group having 2 to 10 carbon atoms.

  Such an active energy ray cross-linking resin is preferably contained in an amount of 0.8% by mass to 5.0% by mass with respect to the total mass of the ink. The presence of 0.8% by mass or more improves cross-linking efficiency, and beading and color bleeding are more preferable due to a rapid increase in ink viscosity after cross-linking. In the case of 5.0% by mass or less, it is difficult to adversely affect the physical properties of the ink and the state in the ink head, which is preferable from the viewpoint of the light emission property and the ink storage property.

  In the active energy ray cross-linking resin of the present invention, the main chain having a certain degree of polymerization is cross-linked through a cross-linking bond between side chains, and thus polymerizes through a general chain reaction. The effect of increasing the molecular weight per photon is significantly greater than that of an active energy ray-curable resin. On the other hand, in the conventionally known active energy ray curable resins, since the number of crosslinking points cannot be controlled, the physical properties of the cured film cannot be controlled, and the film tends to be hard and brittle.

  In the resin used in the present invention, the number of crosslinking points can be completely controlled by the length of the hydrophilic main chain and the amount of side chains introduced, and the physical properties of the ink film can be controlled according to the purpose.

  Furthermore, since almost all of the conventionally known active energy ray-curable ink is curable, except for the color material, the dot portion after curing is prominent and tends to be an excessively glossy image, which is not preferable in terms of image quality. In the resin used, the amount of the curing component is small, the image quality after drying is improved, and the fixability is also good.

<Photopolymerization initiator, sensitizer>
In the present invention, it is also preferable to add a photopolymerization initiator or a sensitizer. These compounds may be dissolved or dispersed in a solvent, or may be chemically bonded to the photosensitive resin.

  There is no restriction | limiting in particular about the photoinitiator and photosensitizer which are applied, A conventionally well-known thing can be used. A water-soluble compound is preferable from the viewpoints of miscibility and reaction efficiency. In particular, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone (HMPK), thioxanthone ammonium salt (QTX), and benzophenone ammonium salt (ABQ) are preferable from the viewpoint of miscibility with an aqueous solvent.

  Furthermore, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone (n = 1, HMPK) represented by the following general formula (7) from the viewpoint of compatibility with the resin, The ethylene oxide adduct (n = 2 to 5) is more preferable.

  In the formula, n represents an integer of 1 to 5.

  Other examples include benzophenones such as benzophenone, hydroxybenzophenone, bis-N, N-dimethylaminobenzophenone, bis-N, N-diethylaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone. Thioxanthones such as thioxatone, 2,4-diethylthioxanthone, isopropylthioxanthone, chlorothioxanthone, and isopropoxychlorothioxanthone. Anthraquinones such as ethyl anthraquinone, benzanthraquinone, aminoanthraquinone and chloroanthraquinone. Acetophenones. Benzoin ethers such as benzoin methyl ether. 2,4,6-trihalomethyltriazines, 1-hydroxycyclohexyl phenyl ketone, 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di ( m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-phenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-phenylimidazole dimer, 2- (P-methoxyphenyl) -4,5-diphenylimidazole dimer, 2, -di (p-methoxyphenyl) -5-phenylimidazole dimer, 2- (2,4-dimethoxyphenyl) -4,5 -2,4,5-triarylimidazole dimer of diphenylimidazole dimer, benzyldimethyl ketal, 2-benzyl-2-dimethyl Amino-1- (4-morpholinophenyl) butan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-propanone, 2-hydroxy-2-methyl-1-phenyl -Propan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, phenanthrenequinone, 9,10-phenanthrenequinone, Benzoins such as methylbenzoin and ethylbenzoin, 9-phenylacridine, acridine derivatives such as 1,7-bis (9,9'-acridinyl) heptane, bisacylphosphine oxide, and mixtures thereof are preferably used. May be used alone or in combination.

  In addition to these photopolymerization initiators, accelerators and the like can also be added. Examples of these include ethyl p-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, ethanolamine, diethanolamine, triethanolamine and the like. Even if these photoinitiators are grafted to the side chain with respect to the hydrophilic main chain.

<Active energy rays, irradiation method>
The active energy ray as used in the present invention includes, for example, electron beam, ultraviolet ray, α ray, β ray, γ ray, X ray and the like. However, it is dangerous to human body, easy to handle, and industrially used. Electron beams and ultraviolet rays are widely used.

  When using an electron beam, the amount of the electron beam to be irradiated is preferably in the range of 0.1 to 30 Mrad. If it is less than 0.1 Mrad, a sufficient irradiation effect cannot be obtained, and if it exceeds 30 Mrad, the support may be deteriorated, which is not preferable.

  When using ultraviolet rays, the light source is a low pressure, medium pressure, high pressure mercury lamp, metal halide lamp, xenon lamp having a light emission wavelength in the ultraviolet region, cold cathode tube, hot cathode tube, for example, having an operating pressure of 0.1 kPa to 1 MPa. A conventionally well-known thing, such as LED, is used.

(Light irradiation conditions after ink landing)
As the irradiation condition of actinic rays, actinic rays are preferably irradiated between 0.001 and 1.0 seconds after ink landing, and more preferably 0.001 to 0.5 seconds. In order to form a high-definition image, it is particularly important that the irradiation timing is as early as possible.

(Installation of lamp)
As a method for irradiating actinic rays, the basic method is disclosed in JP-A-60-132767. According to this, the light source is provided on both sides of the head unit, and the head and the light source are scanned by the shuttle method. Irradiation is performed after a certain period of time after ink landing. Further, the curing is completed by another light source that is not driven. In US Pat. No. 6,145,979, as an irradiation method, a method using an optical fiber or a method of applying a collimated light source to a mirror surface provided on the side of the head unit and irradiating the recording unit with UV light is disclosed. Yes. Any of these irradiation methods can be used in the image forming method of the present invention.

  In another preferred embodiment, irradiation with actinic rays is divided into two stages, and actinic rays are first irradiated by the above-described method between 0.001 and 2.0 seconds after ink landing, and further irradiated with actinic rays. It is. By dividing the irradiation of actinic rays into two stages, it is possible to further suppress the shrinkage of the recording medium that occurs during ink curing.

<Colorant (coloring material)>
As the color material used in the ink jet ink of the present invention, it is preferable to use a dye or a pigment.

(dye)
There is no restriction | limiting in particular as dye which can be used by this invention, Water-soluble dyes, such as an acid dye, a direct dye, and a reactive dye, a disperse dye, etc. are mentioned.

  Specific examples of dyes applicable to the ink jet ink of the present invention are listed below, but the present invention is not limited to these exemplified dyes.

Water-soluble dye Examples of the water-soluble dye that can be used in the present invention include azo dyes, methine dyes, azomethine dyes, xanthene dyes, quinone dyes, phthalocyanine dyes, triphenylmethane dyes, and diphenylmethane dyes.

C. I. Acid Yellow 1, 3, 11, 17, 18, 19, 23, 25, 36, 38, 40, 42, 44, 49, 59, 61, 65, 67, 72, 73, 79, 99, 104, 110, 114, 116, 118, 121, 127, 129, 135, 137, 141, 143, 151, 155, 158, 159, 169, 176, 184, 193, 200, 204, 207, 215, 219, 220, 230, 232, 235, 241, 242, 246
C. I. Acid Orange 3, 7, 8, 10, 19, 24, 51, 56, 67, 74, 80, 86, 87, 88, 89, 94, 95, 107, 108, 116, 122, 127, 140, 142, 144, 149, 152, 156, 162, 166, 168
C. I. Acid Red 88, 97, 106, 111, 114, 118, 119, 127, 131, 138, 143, 145, 151, 183, 195, 198, 211, 215, 217, 225, 226, 249, 251, 254, 256, 257, 260, 261, 265, 266, 274, 276, 277, 289, 296, 299, 315, 318, 336, 337, 357, 359, 361, 362, 364, 366, 399, 407, 415
C. I. Acid Violet 17, 19, 21, 42, 43, 47, 48, 49, 54, 66, 78, 90, 97, 102, 109, 126
C. I. Acid Blue 1, 7, 9, 15, 23, 25, 40, 62, 72, 74, 80, 83, 90, 92, 103, 104, 112, 113, 114, 120, 127, 128, 129, 138, 140, 142, 156, 158, 171, 182, 185, 193, 199, 201, 203, 204, 205, 207, 209, 220, 221, 224, 225, 229, 230, 239, 249, 258, 260, 264, 278, 279, 280, 284, 290, 296, 298, 300, 317, 324, 333, 335, 338, 342, 350
C. I. Acid Green 9, 12, 16, 19, 20, 25, 27, 28, 40, 43, 56, 73, 81, 84, 104, 108, 109,
C. I. Acid Brown 2, 4, 13, 14, 19, 28, 44, 123, 224, 226, 227, 248, 282, 283, 289, 294, 297, 298, 301, 355, 357, 413,
C. I. Acid Black 1, 2, 3, 24, 26, 31, 50, 52, 58, 60, 63, 107, 109, 112, 119, 132, 140, 155, 172, 187, 188, 194, 207, 222,
C. I. Direct yellow 8, 9, 10, 11, 12, 22, 27, 28, 39, 44, 50, 58, 79, 86, 87, 98, 105, 106, 130, 132, 137, 142, 147, 153,
C. I. Direct Orange 6, 26, 27, 34, 39, 40, 46, 102, 105, 107, 118,
C. I. Direct Red 2, 4, 9, 23, 24, 31, 54, 62, 69, 79, 80, 81, 83, 84, 89, 95, 212, 224, 225, 226, 227, 239, 242, 243, 254,
C. I. Direct violet 9, 35, 51, 66, 94, 95
C. I. Direct Blue 1, 15, 71, 76, 77, 78, 80, 86, 87, 90, 98, 106, 108, 160, 168, 189, 192, 193, 199, 200, 201, 202, 203, 218, 225, 229, 237, 244, 248, 251, 270, 273, 274, 290, 291
C. I. Direct green 26, 28, 59, 80, 85
C. I. Direct brown 44, 106, 115, 195, 209, 210, 222, 223
C. I. Direct black 17, 19, 22, 32, 51, 62, 108, 112, 113, 117, 118, 132, 146, 154, 159, 169
C. I. Basic Yellow 1, 2, 11, 13, 15, 19, 21, 28, 29, 32, 36, 40, 41, 45, 51, 63, 67, 70, 73, 91,
C. I. Basic orange 2, 21, 22
C. I. Basic Red 1, 2, 12, 13, 14, 15, 18, 23, 24, 27, 29, 35, 36, 39, 46, 51, 52, 69, 70, 73, 82, 109
C. I. Basic violet 1, 3, 7, 10, 11, 15, 16, 21, 27, 39
C. I. Basic Blue 1, 3, 7, 9, 21, 22, 26, 41, 45, 47, 52, 54, 65, 69, 75, 77, 92, 100, 105, 117, 124, 129, 147, 151
C. I. Basic green 1, 4
C. I. Basic brown 1
C. I. Reactive Yellow 2, 3, 7, 15, 17, 18, 22, 23, 24, 25, 27, 37, 39, 42, 57, 69, 76, 81, 84, 85, 86, 87, 92, 95 , 102, 105, 111, 125, 135, 136, 137, 142, 143, 145, 151, 160, 161, 165, 167, 168, 175, 176
C. I. Reactive orange 1, 4, 5, 7, 11, 12, 13, 15, 16, 20, 30, 35, 56, 64, 67, 69, 70, 72, 74, 82, 84, 86, 87, 91 , 92, 93, 95, 107
C. I. Reactive Red 2, 3, 5, 8, 11, 21, 22, 23, 24, 28, 29, 31, 33, 35, 43, 45, 49, 55, 56, 58, 65, 66, 78, 83 , 84, 106, 111, 112, 113, 114, 116, 120, 123, 124, 128, 130, 136, 141, 147, 158, 159, 171, 174, 180, 183, 184, 187, 190, 193 , 194, 195, 198, 218, 220, 222, 223, 228, 235
C. I. Reactive violet 1, 2, 4, 5, 6, 22, 23, 33, 36, 38
C. I. Reactive Blue 2, 3, 4, 5, 7, 13, 14, 15, 19, 21, 25, 27, 28, 29, 38, 39, 41, 49, 50, 52, 63, 69, 71, 72 77, 79, 89, 104, 109, 112, 113, 114, 116, 119, 120, 122, 137, 140, 143, 147, 160, 161, 162, 163, 168, 171, 176, 182, 184 191, 194, 195, 198, 203, 204, 207, 209, 211, 214, 220, 221, 222, 231, 235, 236
C. I. Reactive Green 8, 12, 15, 19, 21
C. I. Reactive Brown 2, 7, 9, 10, 11, 17, 18, 19, 21, 23, 31, 37, 43, 46
C. I. Reactive Black 5, 8, 13, 14, 31, 34, 39
C. I. Food black 1, 2
Etc.

  Furthermore, examples of the dye include a compound represented by the following general formula (8) or a compound represented by the general formula (9).

In the general formula (8), R ₁ represents a hydrogen atom or a substitutable substituent, and is preferably a hydrogen atom or a phenylcarbonyl group. R ₂ may be different and represents a hydrogen atom or a substitutable substituent, and is preferably a hydrogen atom. R ₃ represents a hydrogen atom or a substitutable substituent, and is preferably a hydrogen atom or an alkyl group. R ₄ represents a hydrogen atom or a substitutable substituent, preferably a hydrogen atom or an aryloxy group. R ₅ may be different and represents a hydrogen atom or a substitutable substituent, and is preferably a sulfonic acid group. n represents an integer of 1 to 4, and m represents an integer of 1 to 5.

In the general formula (9), X represents a phenyl group or a naphthyl group, may be substituted with a substitutable substituent, and is preferably substituted with a sulfonic acid group or a carboxyl group. Y represents hydrogen ion, sodium ion, potassium ion, lithium ion, ammonium ion or alkylammonium ion. R ₆ may be different and represents a hydrogen atom or a substituent that can be substituted on the naphthalene ring. q represents 1 or 2. p represents an integer of 1 to 4. However, q + p = 5. Z represents a substitutable substituent, and represents a carbonyl group, a sulfonyl group or a group represented by the following general formula (10), and particularly preferably a group represented by the following general formula (10).

In the general formula (10), W ₁ and W ₂ each independently represent a halogen atom, amino group, hydroxyl group, alkylamino group or arylamino group, preferably a halogen atom, hydroxyl group or alkylamino group.

(Disperse dye)
As the disperse dye, various disperse dyes such as azo disperse dyes, quinone disperse dyes, anthraquinone disperse dyes, quinophthalone disperse dyes can be used, and specific compounds thereof are listed below.

C. I. Disperse Yellow
3, 4, 5, 7, 9, 13, 23, 24, 30, 33, 34, 42, 44, 49, 50, 51, 54, 56, 58, 60, 63, 64, 66, 68, 71, 74, 76, 79, 82, 83, 85, 86, 88, 90, 91, 93, 98, 99, 100, 104, 108, 114, 116, 118, 119, 122, 124, 126, 135, 140, 141, 149, 160, 162, 163, 164, 165, 179, 180, 182, 183, 184, 186, 192, 198, 199, 202, 204, 210, 211, 215, 216, 218, 224, 227, 231,232
C. I. Disperse Orange
1, 3, 5, 7, 11, 13, 17, 20, 21, 25, 29, 30, 31, 32, 33, 37, 38, 42, 43, 44, 45, 47, 48, 49, 50, 53, 54, 55, 56, 57, 58, 59, 61, 66, 71, 73, 76, 78, 80, 89, 90, 91, 93, 96, 97, 119, 127, 130, 139, 142
C. I. Disperse Red
1, 4, 5, 7, 11, 12, 13, 15, 17, 27, 43, 44, 50, 52, 53, 54, 55, 56, 58, 59, 60, 65, 72, 73, 74, 75, 76, 78, 81, 82, 86, 88, 90, 91, 92, 93, 96, 103, 105, 106, 107, 108, 110, 111, 113, 117, 118, 121, 122, 126, 127, 128, 131, 132, 134, 135, 137, 143, 145, 146, 151, 152, 153, 154, 157, 159, 164, 167, 169, 177, 179, 181, 183, 184, 185, 188, 189, 190, 191, 192, 200, 201, 202, 203, 205, 206, 207, 210, 221, 224, 225, 227, 229, 23 , 240,257,258,277,278,279,281,288,298,302,303,310,311,312,320,324,328,
C. I. Disperse Violet
1, 4, 8, 23, 26, 27, 28, 31, 33, 35, 36, 38, 40, 43, 46, 48, 50, 51, 52, 56, 57, 59, 61, 63, 69, 77,
C. I. Disperse Green
9
C. I. Disperse Brown
1, 2, 4, 9, 13, 19
C. I. Disperse Blue
3, 7, 9, 14, 16, 19, 20, 26, 27, 35, 43, 44, 54, 55, 56, 58, 60, 62, 64, 71, 72, 73, 75, 79, 81, 82, 83, 87, 91, 93, 94, 95, 96, 102, 106, 108, 112, 113, 115, 118, 120, 122, 125, 128, 130, 139, 141, 142, 143, 146, 148, 149, 153, 154, 158, 165, 167, 171, 173, 174, 176, 181, 183, 185, 186, 187, 189, 197, 198, 200, 201, 205, 207, 211, 214, 224, 225, 257, 259, 267, 268, 270, 284, 285, 287, 288, 291, 293, 295, 297, 301, 315, 3 0,333
C. I. Disperse Black
1, 3, 10, 24
Etc.

(Pigment)
As the pigment that can be used in the present invention, conventionally known organic and inorganic pigments can be used, but they are anionic pigments. For example, azo pigments such as azo lakes, insoluble azo pigments, condensed azo pigments, chelate azo pigments, phthalocyanine pigments, perylene and perylene pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, thioindigo pigments, isoindolinone pigments, quinophthalone pigments, etc. Examples include cyclic pigments, dye lakes such as acid dye lakes, organic pigments such as nitro pigments, nitroso pigments, aniline black, and daylight fluorescent pigments, and inorganic pigments such as carbon black.

  Specific organic pigments are exemplified below.

  Examples of pigments for magenta or red include C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment red 15, C.I. I. Pigment red 16, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 123, C.I. I. Pigment red 139, C.I. I. Pigment red 144, C.I. I. Pigment red 149, C.I. I. Pigment red 166, C.I. I. Pigment red 177, C.I. I. Pigment red 178, C.I. I. And CI Pigment Red 222.

  Examples of the orange or yellow pigment include C.I. I. Pigment orange 31, C.I. I. Pigment orange 43, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 128, C.I. I. And CI Pigment Yellow 138.

  Examples of pigments for green or cyan include C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 16, C.I. I. Pigment blue 60, C.I. I. And CI Pigment Green 7.

(Pigment dispersion method)
As a method for dispersing the pigment, for example, various dispersing machines such as a ball mill, a sand mill, an attritor, a roll mill, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a wet jet mill, and a paint shaker can be used. It is also preferable to use a centrifugal separator or a filter for the purpose of removing the coarse particles of the pigment dispersion.

  In the ink according to the present invention, a self-dispersed pigment in which polar groups such as sulfonic acid and carboxylic acid are pendant on the pigment surface, or a pigment dispersed using a polymer dispersant is preferable.

  The polymer dispersant according to the present invention is not particularly limited, and a water-soluble resin or a water-insoluble resin is used. Examples of these polymers include styrene, styrene derivatives, vinyl naphthalene derivatives, acrylic acid, acrylic acid derivatives, methacrylic acid, methacrylic acid derivatives, maleic acid, maleic acid derivatives, itaconic acid, itaconic acid derivatives, fumaric acid, fumaric acid. Examples thereof include a polymer composed of a single monomer selected from acid derivatives, a copolymer composed of two or more monomers, and salts thereof. Water-soluble polymers such as polyvinyl alcohol, polyvinyl pyrrolidone, cellulose derivatives, gelatin, and polyethylene glycol can also be used.

The content of these water-soluble resins with respect to the total amount of ink is preferably 0.1 to 10% by mass, and more preferably 0.3 to 5% by mass. These water-soluble resins can be used in combination of two or more.

  The average particle size of the pigment dispersion used in the inkjet ink of the present invention is preferably 500 nm or less, more preferably 200 nm or less, preferably 10 nm or more and 200 nm or less, and more preferably 10 nm or more and 150 nm or less. If the average particle size of the pigment dispersion exceeds 500 nm, the dispersion becomes unstable. In addition, even when the average particle size of the pigment dispersion is less than 10 nm, the stability of the pigment dispersion tends to deteriorate, and the storage stability of the ink tends to deteriorate.

  The particle size of the pigment dispersion can be determined by a commercially available particle size measuring device using a light scattering method, an electrophoresis method, a laser Doppler method or the like. It is also possible to obtain a particle image with a transmission electron microscope on at least 100 particles and perform statistical processing on the image using image analysis software such as Image-Pro (manufactured by Media Cybernetics). Is possible.

<Water-soluble solvent>
As the solvent according to the present invention, an aqueous liquid medium is preferably used, and as the aqueous liquid medium, a mixed solvent such as water and a water-soluble organic solvent is further preferably used. Examples of water-soluble organic solvents that are preferably used include alcohols (eg, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, secondary butanol, tertiary butanol), polyhydric alcohols (eg, ethylene glycol, diethylene glycol, Triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol, thiodiglycol), polyhydric alcohol ethers (eg, ethylene glycol monomethyl ether, ethylene Glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol Nomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, ethylene glycol Monophenyl ether, propylene glycol monophenyl ether), amines (for example, ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, diethylenediamine, triethylenetetra) , Tetraethylenepentamine, polyethyleneimine, pentamethyldiethylenetriamine, tetramethylpropylenediamine), amides (eg, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, etc.), heterocycles (eg, 2 -Pyrrolidone, N-methyl-2-pyrrolidone, cyclohexyl pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone), sulfoxides (for example, dimethyl sulfoxide) and the like.

<Surfactant>
Surfactants preferably used in the ink of the present invention include alkyl sulfates, alkyl ester sulfates, dialkyl sulfosuccinates, alkyl naphthalene sulfonates, alkyl phosphates, polyoxyalkylene alkyl ether phosphates, fatty acids. Anionic surfactants such as salts, nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyalkylene alkyl phenyl ethers, acetylene glycols, polyoxyethylene-polyoxypropylene block copolymers, glycerin esters, sorbitan Activators such as esters, polyoxyethylene fatty acid amides and amine oxides, and cationic surfactants such as alkylamine salts and quaternary ammonium salts.

  These surfactants can also be used as pigment dispersants, and in particular, anionic and nonionic surfactants can be preferably used.

<Various additives>
In the present invention, other conventionally known additives can be contained. For example, optical brighteners, antifoaming agents, lubricants, preservatives, thickeners, antistatic agents, matting agents, water-soluble polyvalent metal salts, acid bases, pH adjusters such as buffer solutions, antioxidants, surface tension They are regulators, non-resistance regulators, rust inhibitors, inorganic pigments and the like.

<Recording sheet>
The paper, coated paper, there is a non-coated paper, as the coated paper, the coating amount per 1m ² is one side 20g before and after of art paper, 1m ² per coated amount on one side 10g before and after the coated paper Examples include a light-weight coated paper having a coating amount per 1 m ^{2 of} about 5 g on one side, a finely coated paper, a mat-like finished mat-coated paper, a dull-like finished dull-coated paper, and a newsprint. Non-coated paper includes printing paper A using 100% chemical pulp, printing paper B using 70% or more chemical pulp, printing paper C using 40% or more and less than 70% chemical pulp, and printing using less than 40% chemical pulp. Examples thereof include paper D, gravure paper containing mechanical pulp and subjected to calendar treatment. Further details are described in detail in the “Latest Paper Processing Handbook” edited by the Paper Processing Handbook Editorial Committee, published by Tech Times, “Printing Engineering Handbook” edited by the Japan Printing Society.

  The plain paper is 80 to 200 μm uncoated paper belonging to a part of uncoated paper, special printing paper and information paper. The plain paper used in the present invention includes, for example, high-grade printing paper, intermediate-grade printing paper, low-grade printing paper, thin-like printing paper, fine-coating printing paper, special printing paper such as fine-quality printing paper, foam paper, PPC paper, and others There are information sheets and the like. Specifically, there are the following sheets and various modified / processed sheets using these sheets, but the present invention is not particularly limited thereto. High quality paper and colored high quality paper, recycled paper, copy paper / colored paper, OCR paper, carbonless paper / colored paper, synthetic paper such as YUPO 60, 80, 110 microns, YUPO COAT 70, 90 microns, etc. Coated paper 90kg, Foam mat paper 70, 90, 110kg, Foamed PET 38 microns, Mitsuori-kun (above, Kobayashi recording paper), OK fine paper, New OK fine paper, Sunflower, Phoenix, OK Royal White, Export fine paper ( NPP, NCP, NWP, Royal White) OK Book Paper, OK Cream Book Paper, Cream Premium Paper, OK Map Paper, OK Ishikari, Cucumber, OK Foam, OKH, NIP-N (above, Shin Oji Paper), Gold Wang, Toko, export quality paper, special demand quality paper, book paper, book paper L, light cream book paper, elementary textbook Paper, continuous slip paper, high quality NIP paper, silver ring, gold yang, gold yang (W), bridge, capital, silver ring book, harp, harp cream, SK color, securities paper, opera cream, opera, KYP medical record, silvia HN, Excellent Foam, NPI Foam DX (Nippon Paper), Pearl, Kinryo, Uscream fine paper, Special Book Paper, Super Book Paper, Book Paper, Diamond Foam, Inkjet Foam (Mitsubishi Paper), Carpet V, carpet SW, white elephant, luxury publication paper, cream carpet, cream white elephant, securities / voucher paper, book paper, map paper, copy paper, HNF (above, Hokuetsu), phone book cover, Book paper, cream shirairai, cream shirairaifu, cream shirairaifu, DSK (above, Daishowa Paper), Sendai MP fine paper, Jiang, Thunderbird fine, hanging paper, colored paper base, dictionary paper, cream book, white book, cream fine paper, map paper, continuous slip paper (above, Chuetsu Pulp), OP gold cherry (Chuetsu), gold sand, reference book paper, Replacement certificate paper (white), form printing paper, KRF, white foam, color foam, (K) NIP, fine PPC, Kishu inkjet paper (above, made by Kishu Paper), Taiou, Bright Foam, Kant, Kant White, Dante , CM paper, Dante comic, Heine, paperback book paper, Heine S, New AD paper, Utrilo Excel, Excel Super A, Kant Excel, Excel Super B, Dante Excel, Heine Excel, Excel Super C, Excel Super D, AD Excel, Excel Super E, New Bright Foam, New Bright NI P (above, made by Daio Paper), Sun Ring, Moon Ring, Cloud Pass, Galaxy, Baiyun, Wyeth, Moon Ring Ace, Baiyun Ace, Cloud Pass Ace (above, Nippon Paper Industries), Taiou, Bright Foam, Bright Nip (Nagoya Pulp), Peony A, Golden Pigeon, Special Peony, White Peony A, White Peony C, Silver Pigeon, Super White Peony A, Light Cream White Peony, Special Medium Quality Paper, White Pigeon, Super Medium Quality Paper, Blue Pigeon, Red Pigeon, Gold Pigeon M Snow Vision, Snow Vision, Gold Pigeon Snow Vision, White Pigeon M, Super DX, Hamanasu O, Red Pigeon M, HK Super Printing Paper (above, Honshu Paper), Stalinden (A・ AW), Star Elm, Star Maple, Star Laurel, Star Poplar, MOP, Star Cherry I, Cherry I Super, Cherry II Super, Star Cherry III, Star Cherry IV, Cherry III Super, Cheri -IV Super (above, made by Maruzumi Paper), SHF (above, made by Toyo Pulp), TRP (above, made by Tokai Pulp) and the like.

(Various films)
As the various films, all commonly used films can be used. For example, there are a polyester film, a polyolefin film, a polyvinyl chloride film, a polyvinylidene chloride film, and the like. Resin-coated paper that is photographic printing paper or YUPO paper that is synthetic paper can also be used.

(Various ink jet recording media)
As the various ink jet recording media, an ink receiving layer is formed on the surface using an absorbent support or a non-absorbent support as a base material. Examples of the ink receiving layer include a coating layer, a swelling layer, and a fine void layer.

  The swelling layer absorbs ink when the ink receiving layer made of a water-soluble polymer swells. The fine void layer is composed of inorganic or organic fine particles having a secondary particle size of about 20 to 200 nm and a binder, and fine voids of about 100 nm absorb ink.

  In recent years, an inkjet recording medium in which the above-mentioned fine void layer is provided on a base material using RC paper in which both sides of a paper base material are coated with an olefin resin is preferably used in terms of photographic images.

  Examples of the present invention will be described below, but the present invention is not limited to these examples. Unless otherwise specified in the text, “part” means “part by mass”, and “%” means “% by mass”.

<Synthesis of Polymer Compound 1>
56 g of glycidyl methacrylate, 48 g of p-hydroxybenzaldehyde, 2 g of pyridine, and 1 g of N-nitroso-phenylhydroxyamine ammonium salt were put in a reaction vessel, respectively, and stirred in an 80 ° C. hot water bath for 8 hours.

  Next, 45 g of silanol-modified PVA (Kuraray R2105) was dispersed in 225 g of ion-exchanged water, and then 4.5 g of phosphoric acid and p- (3-methacryloxy-2-hydroxypropyl) obtained by the above reaction were added to this solution. Oxy) benzaldehyde was added under the condition that the modification rate was 3 mol% with respect to the saponified polyvinyl acetate, and the mixture was stirred at 90 ° C. for 6 hours. After cooling the resulting solution to room temperature, 30 g of basic ion exchange resin was added and stirred for 1 hour. Next, the ion exchange resin was filtered, and Irgacure 2959 (manufactured by Ciba Specialty Chemicals) was mixed here as a photopolymerization initiator at a ratio of 0.1 g with respect to 100 g of a 15% aqueous solution. Dilution was performed to obtain a 10% aqueous solution of polymer compound 1.

<Synthesis of polymer compound 2>
A 10% aqueous solution of polymer compound 2 was obtained in the same manner as polymer compound 1 except that the active energy ray cross-linking group modification rate of silanol-modified PVA was changed to 0.4 mol% in the synthesis of polymer compound 1.

<Synthesis of Polymer Compound 3>
A 10% aqueous solution of polymer compound 3 was obtained in the same manner as polymer compound 1 except that the active energy ray cross-linking group modification rate of silanol-modified PVA was changed to 4.5 mol% in the synthesis of polymer compound 1.

<Preparation of ink>
(Preparation of pigment dispersion)
Preparation of Yellow Pigment Dispersion A yellow pigment dispersion having a 10% yellow pigment content by mixing the following additives and dispersing using a sand grinder filled with 50% by volume of 0.5 mm zirconia beads. Was prepared.

C. I. Pigment Yellow 74 95g
Demall C (Kao Corporation) 65g
Ethylene glycol 100g
Ion exchange water 120g
Preparation of magenta pigment dispersion A magenta pigment dispersion having a 10% magenta pigment content by mixing the following additives and dispersing using a sand grinder filled with 50% by volume of 0.5 mm zirconia beads. Was prepared. The average particle size of the magenta pigment particles contained in this magenta pigment dispersion was 83 nm. The particle size was measured using a Zetasizer 1000HS manufactured by Malvern.

C. I. Pigment Red 122 10 parts Jonkrill 61 (acrylic styrene resin dispersant, manufactured by Johnson) 3 parts Glycerin 15 parts Ion-exchanged water 72 parts Preparation of cyan pigment dispersion The following additives were mixed and 0.5 mm zirconia The beads were dispersed using a sand grinder filled with 50% by volume to prepare a cyan pigment dispersion having a cyan pigment content of 10%.

C. I. Pigment Blue 15: 3 100g
DEMAL C 68g
Diethylene glycol 100g
125g of ion exchange water
Preparation of Black Pigment Dispersion Liquid Each of the following additives was mixed and dispersed using a sand grinder filled with 50% by volume of 0.5 mm zirconia beads to obtain a black pigment dispersion liquid having a black pigment content of 10%. Was prepared.

Talker Black # 8500 (Tokai Carbon Co., Ltd.) 120g
Jongkrill 62 (Johnson Polymer) 59g
Lebenol WX (Kao Corporation) 3g
Diethylene glycol 100g
Ion exchange water 300g
Ink sets 1 to 7 for each pigment / dye were prepared in the following combinations.

<Preparation of ink set 1>
Ink set 1 including yellow ink Y1, magenta ink M1, cyan ink C1, and black ink K1 was produced as follows.

(Preparation of yellow ink Y1)
Yellow pigment dispersion 30 parts 10% aqueous solution of polymer compound 1 20 parts Adipic acid hydrazide 0.1 parts Glycerol 7 parts Ethylene glycol 15 parts Diethylene glycol monobutyl ether 2 parts Olfine e1010 (manufactured by Nisshin Chemical Co., Ltd.) 0.2 parts or more Ion exchange water was added to make a total amount of 100 parts, and yellow ink Y1 was produced.

(Preparation of magenta ink M1)
Magenta ink M1 was produced in the same manner as yellow ink Y1, except that the yellow pigment dispersion was changed to a magenta pigment dispersion in the production of yellow ink Y1.

(Preparation of cyan ink C1)
A cyan ink C1 was produced in the same manner as the yellow ink Y1, except that the yellow pigment dispersion was changed to a cyan pigment dispersion in the production of the yellow ink Y1.

(Preparation of black ink K1)
Black pigment dispersion 30 parts 10% aqueous solution of polymer compound 1 20 parts Adipic acid hydrazide 0.1 parts Glycerol 7 parts Ethylene glycol 15 parts Diethylene glycol monobutyl ether 2 parts Olfine e1010 (manufactured by Nisshin Chemical Co., Ltd.) 0.2 parts or more Ion-exchanged water was added to make a total amount of 100 parts to prepare a black ink K1.

<Preparation of ink set 2>
Ink set 2 composed of yellow ink Y2, magenta ink M2, cyan ink C2, and black ink K2 was produced as follows.

(Preparation of yellow ink Y2)
A yellow ink Y2 was prepared in the same manner as in the preparation of the yellow ink Y1, except that a 10% aqueous solution of the polymer compound 2 was used instead of the 10% aqueous solution of the polymer compound 1.

(Preparation of magenta ink M2)
Magenta ink M2 was produced in the same manner as in the production of magenta ink M1, except that a 10% aqueous solution of polymer compound 2 was used instead of the 10% aqueous solution of polymer compound 1.

(Preparation of cyan ink C2)
Cyan ink C2 was produced in the same manner as in the production of cyan ink C1, except that a 10% aqueous solution of polymer compound 2 was used instead of the 10% aqueous solution of polymer compound 1.

(Preparation of black ink K2)
Black ink K2 was produced in the same manner as in the production of black ink K1, except that a 10% aqueous solution of polymer compound 2 was used instead of the 10% aqueous solution of polymer compound 1.

<Preparation of ink set 3>
Ink set 3 including yellow ink Y3, magenta ink M3, cyan ink C3, and black ink K3 was produced as follows.

(Preparation of yellow ink Y3)
A yellow ink Y3 was prepared in the same manner as in the preparation of the yellow ink Y1, except that a 10% aqueous solution of the polymer compound 3 was used instead of the 10% aqueous solution of the polymer compound 1.

(Preparation of magenta ink M3)
Magenta ink M3 was produced in the same manner as in the production of magenta ink M1, except that a 10% aqueous solution of polymer compound 3 was used instead of the 10% aqueous solution of polymer compound 1.

(Preparation of cyan ink C3)
Cyan ink C3 was prepared in the same manner as in the preparation of cyan ink C1, except that a 10% aqueous solution of polymer compound 3 was used instead of the 10% aqueous solution of polymer compound 1.

(Preparation of black ink K3)
A black ink K3 was produced in the same manner as in the production of the black ink K1, except that a 10% aqueous solution of the polymer compound 3 was used instead of the 10% aqueous solution of the polymer compound 1.

<Preparation of ink set 4>
Ink set 4 composed of yellow ink Y4, magenta ink M4, cyan ink C4, and black ink K4 was produced as follows.

(Preparation of yellow ink Y4)
Yellow pigment dispersion 30 parts 10% aqueous solution of polymer compound 1 5 parts Adipic acid hydrazide 0.02 parts Glycerol 7 parts Ethylene glycol 15 parts Diethylene glycol monobutyl ether 2 parts Olfine e1010 (manufactured by Nisshin Chemical Co., Ltd.) 0.2 parts or more Ion exchange water was added to make a total amount of 100 parts, and yellow ink Y4 was produced.

(Preparation of magenta ink M4)
A magenta ink M4 was produced in the same manner as the yellow ink Y4 except that the yellow pigment dispersion was changed to a magenta pigment dispersion in the production of the yellow ink Y4.

(Preparation of cyan ink C4)
A cyan ink C4 was produced in the same manner as the yellow ink Y4 except that the yellow pigment dispersion was changed to a cyan pigment dispersion in the production of the yellow ink Y4.

(Preparation of black ink K4)
A black ink K4 was produced in the same manner as the yellow ink Y4 except that the yellow pigment dispersion was changed to a black pigment dispersion in the production of the yellow ink Y4.

<Preparation of ink set 5>
Ink set 5 composed of yellow ink Y5, magenta ink M5, cyan ink C5, and black ink K5 was produced as follows.

(Preparation of yellow ink Y5)
Yellow pigment dispersion 30 parts 12% aqueous solution of polymer compound 1 (concentrated) 43 parts Adipic acid hydrazide 0.2 parts Glycerol 7 parts Ethylene glycol 15 parts Diethylene glycol monobutyl ether 2 parts Olphine e1010 (manufactured by Nisshin Chemical Co., Ltd.) 0 .2 parts Ion-exchanged water was added to make 100 parts in total, and yellow ink Y5 was produced.

(Preparation of magenta ink M5)
A magenta ink M5 was produced in the same manner as the yellow ink Y5 except that the yellow pigment dispersion was changed to a magenta pigment dispersion in the production of the yellow ink Y5.

(Preparation of cyan ink C5)
A cyan ink C5 was produced in the same manner as the yellow ink Y5 except that the yellow pigment dispersion was changed to a cyan pigment dispersion in the production of the yellow ink Y5.

(Preparation of black ink K5)
A black ink K5 was produced in the same manner as the yellow ink Y5 except that the yellow pigment dispersion was changed to a black pigment dispersion in the production of the yellow ink Y5.

<Preparation of ink set 6>
Ink set 6 composed of yellow ink Y6, magenta ink M6, cyan ink C6 and black ink K6 was produced as follows.

(Preparation of yellow ink Y6)
C. I. Pigment Yellow 74 10 parts Azisper PB821 (manufactured by Ajinomoto Fine Techno Co., Ltd.) 3 parts Aronix M5700 (manufactured by Toagosei Co., Ltd.) 7 parts Ethylene oxide added 1,6 hexanediol acrylate 72 parts 3-methoxybutyl acrylate 8 parts Irgacure 369 (Ciba Specialty Chemicals) Product) 5 parts After mixing and stirring each of the above compositions, the resulting solution was filtered through a filter to prepare actinic ray curable yellow ink Y6.

(Preparation of magenta ink M6)
C. I. Pigment Red122 10 parts Azisper PB821 (Ajinomoto Fine Techno Co., Ltd.) 3 parts Aronix M5700 (Toagosei Co., Ltd.) 7 parts Ethylene oxide added 1,6 hexanediol acrylate 72 parts 3-methoxybutyl acrylate 8 parts Irgacure 369 (Ciba Specialty Chemicals) 5 parts After mixing and stirring each of the above compositions, the resulting solution was filtered through a filter to prepare actinic ray curable magenta ink M6.

(Preparation of cyan ink C6)
C. I. Pigment Blue 15: 3 10 parts Azisper PB821 (Ajinomoto Fine Techno Co., Ltd.) 3 parts Aronix M5700 (Toagosei Co., Ltd.) 7 parts Ethylene oxide added 1,6 hexanediol acrylate 72 parts 3-methoxybutyl acrylate 8 parts Irgacure 369 (Ciba Specialty) Chemical Co., Ltd.) 5 parts After mixing and stirring each of the above compositions, the resulting solution was filtered with a filter to prepare actinic ray curable cyan ink C6.

(Preparation of black ink K6)
Carbon black (Mitsubishi Chemical Corporation, MA-7) 10 parts Azisper PB821 (Ajinomoto Fine Techno Co., Ltd.) 3 parts Aronix M5700 (Toagosei Co., Ltd.) 7 parts Ethylene oxide added 1,6 hexanediol acrylate 72 parts 3-methoxybutyl acrylate 8 parts Irgacure 369 (manufactured by Ciba Specialty Chemicals) 5 parts After mixing and stirring each of the above compositions, the resulting solution was filtered through a filter to prepare actinic ray curable black ink K6.

  Hereinafter, a dye-type ink set 7 was produced.

<Preparation of ink set 7>
Ink set 7 composed of yellow ink Y7, magenta ink M7, cyan ink C7, and black ink K7 was produced as follows.

(Preparation of yellow ink Y7)
C. I. Acid Yellow 23 3 parts 10% aqueous solution of polymer compound 1 20 parts Glycerol 7 parts Ethylene glycol 15 parts Diethylene glycol monobutyl ether 2 parts Olphine e1010 (manufactured by Nissin Chemical Co., Ltd.) 0.2 parts A yellow ink Y7 was produced.

(Preparation of magenta ink M7)
In the production of yellow ink Y7, C.I. I. Acid Yellow 23 is C.I. I. A magenta ink M7 was produced in the same manner as the yellow ink Y7, except that it was changed to Direct Red227.

(Preparation of cyan ink C7)
In the production of yellow ink Y7, C.I. I. Acid Yellow 23 is C.I. I. A cyan ink C7 was produced in the same manner as the yellow ink Y7, except that it was changed to Direct Blue 199.

(Preparation of black ink K7)
C. I. Food Black 2 4 parts 10% aqueous solution of polymer compound 1 20 parts Glycerol 7 parts Ethylene glycol 15 parts Diethylene glycol monobutyl ether 2 parts Orphine e1010 (manufactured by Nissin Chemical Co., Ltd.) 0.2 parts A black ink K7 was produced.

  The following evaluation was performed for ink sets 1 to 7.

<Performance evaluation>
The results are summarized in Table 1 below together with the ink composition and combination.

(Evaluation of beading resistance)
An on-demand type with a maximum recording density of 720 × 720 dpi using a piezo head having a nozzle diameter of 25 μm, a drive frequency of 12 kHz, a nozzle count of 128, and a nozzle density of 180 dpi (dpi is the number of dots in a width of 2.54 cm). Using an inkjet printer, 5 cm × 5 cm magenta solids were printed on art paper (SA Kinfuji, Oji Paper Co., Ltd.) and visually observed, and beading resistance was evaluated according to the following criteria.

  In addition, each ink was continuously ejected, and 0.1 seconds after landing, 120 W / cm metal halide lamps (MAL 400NL manufactured by Nihon Battery Co., Ltd., power supply power 3 kW · hr) disposed at both ends of the piezoelectric head were irradiated.

◎: Uniform image ○: Mottled noise that can be seen when viewed closely is present in less than 5 points Δ: Mottled noise that can be understood when viewed carefully is present in less than 10 points ×: Clear mottled noise is 10 Existence of more than one place XX: More than 20 mottled noises exist. Among these, x and xx are levels that are problematic as products.

(Evaluation of bleed resistance)
Using an on-demand inkjet printer with a maximum recording density of 720 x 720 dpi, using a piezo-type head with a nozzle diameter of 25 μm, a drive frequency of 12 kHz, a nozzle count of 128, and a nozzle density of 180 dpi, on art paper (SA Kanto, Oji Paper) A black thin line having a width of 200 μm was printed on a magenta solid, then visually observed, and bleed resistance was evaluated according to the following criteria.

  In addition, each ink was continuously ejected, and 0.1 seconds after landing, 120 W / cm metal halide lamps (MAL 400NL manufactured by Nihon Battery Co., Ltd., power supply power 3 kW · hr) disposed at both ends of the piezoelectric head were irradiated.

◎: The boundary between the fine line and the solid is clear. ○: The boundary is slightly blurred, but there is no problem in practical use. △: The boundary is blurred, but practically acceptable. ×: Obvious blurring is observed at the boundary, the line width is about 1.5 times, and this is a quality that is a practical problem. XX: The boundary between the thin line and the solid part is unclear. Quality and extremely low bleed resistance (Evaluation of image smoothness)
Using an on-demand inkjet printer with a maximum recording density of 720 x 720 dpi, using a piezo-type head with a nozzle diameter of 25 μm, a drive frequency of 12 kHz, a nozzle count of 128, and a nozzle density of 180 dpi, on art paper (SA Kanto, Oji Paper) N3 “fruit basket” of a high-definition color digital standard image conforming to JIS X 9201-1995 was printed, visually observed, and image smoothness was evaluated according to the following criteria.

  In addition, each ink was continuously ejected, and after landing, 0.1 seconds later, 120 W / cm metal halide lamps (MAL 400NL, power source power 3 kW · hr, manufactured by Nihon Battery Co., Ltd.) disposed at both ends of the piezoelectric head were irradiated.

A: There is almost no difference in smoothness between the recording surface and the background, and it is natural. ○: The smoothness of the recording surface and the background is slightly different, but an acceptable level. No ×: The surface of the recording surface is observed to be rough, and there is clearly no smoothness. XX: A large rough feeling is felt not only by visual inspection but also by palpation (evaluation of water resistance)
A piezo-type head with a nozzle diameter of 25 μm, a drive frequency of 12 kHz, a nozzle count of 128, and a nozzle density of 180 dpi. Each ink set is mounted on an on-demand type ink jet printer with a maximum recording density of 720 × 720 dpi, and art paper (Oji Paper) 10 cm × 10 cm of cyan solid was printed on (SA Kinfuji Co., Ltd.).

  In addition, 0.1 seconds after the ink was continuously ejected and landed, a 120 W / cm metal halide lamp (MAL 400NL manufactured by Nippon Battery Co., Ltd., power supply power 3 kW · hr) was irradiated to prepare an evaluation image sample.

  The surface of the image sample produced as described above was rubbed 5 times with BEMCOT (manufactured by Asahi Kasei) containing pure water, the degree of image density reduction was visually observed, and water resistance was evaluated according to the following criteria.

◎: No color fading is observed at all. ○: Some color fading is observed, but the image is not a concern. △: Color fading is slightly confirmed, and a slight decrease in image quality is observed, but acceptable in practice. Within the possible range ×: Color loss is large, the effect on image quality is large, and the quality is outside the acceptable range for practical use. XX: Color loss is quite large, the image is severely soiled, and it cannot be used practically. Table 1 shows.

(Evaluation of fixability)
A piezo-type head with a nozzle diameter of 25 μm, a drive frequency of 12 kHz, a nozzle count of 128, and a nozzle density of 180 dpi. Each ink set is mounted on an on-demand type ink jet printer with a maximum recording density of 720 × 720 dpi, and art paper (Oji Paper) 10 cm × 10 cm of cyan solid was printed on (SA Kanofuji).

  In addition, 0.1 seconds after the ink was continuously ejected and landed, a 120 W / cm metal halide lamp (MAL 400NL manufactured by Nippon Battery Co., Ltd., power supply power 3 kW · hr) was irradiated to prepare an evaluation image sample.

  After the image sample produced as described above was rubbed 10 times with an eraser (plastic eraser manufactured by KOKUYO), the presence or absence of stains on the printed portion was visually observed, and scratch resistance was evaluated according to the following criteria.

◎: No change in the printed image ○: Slight stain is observed in the printed image when observed in detail △: Stain is slightly observed in the printed image, but is in a practically acceptable range ×: The printed image Stain is clearly observed and the quality is outside the acceptable range for practical use. XX: Printed image is very dirty and cannot be used practically (evaluation of glossiness)
Using an on-demand inkjet printer with a maximum recording density of 720 x 720 dpi, using a piezo-type head with a nozzle diameter of 25 μm, a drive frequency of 12 kHz, a nozzle count of 128, and a nozzle density of 180 dpi, on art paper (SA Kanto, Oji Paper) A black solid of 10 cm × 10 cm was printed, visually observed, and glossiness was evaluated according to the following criteria.

  In addition, each ink was continuously ejected, and after landing for 0.1 seconds, 120 W / cm metal halide lamps (MAL 400NL power supply power 3 kW · hr, manufactured by Nihon Battery Co., Ltd.) disposed at both ends of the piezoelectric head were irradiated.

◎: Natural difference between glossiness of recording surface and background is almost natural ○: Glossiness of recording surface and background is slightly different, but acceptable level Δ: Visual observation that glossiness of recording surface and background is slightly different And the glossiness of the recording surface is remarkably higher than that of the background. X: It is possible to visually observe that the glossiness of the recording surface and the background is clearly different, and the glossiness of the recording surface is remarkably higher than that of the background. Can be observed visually, and the glossiness of the recording surface is significantly lower than the base

    *: Ethylene oxide-added 1,6-hexanediol acrylate

Claims (8)

In an inkjet ink containing at least a coloring material, water, and a polymer compound having a side chain that is crosslinked by irradiating an active energy ray to a hydrophilic main chain, and capable of crosslinking between the side chains,
An ink-jet ink, wherein the hydrophilic main chain is silanol-modified polyvinyl alcohol . The inkjet ink according to claim 1, wherein the polymer compound is contained in an amount of 0.8 to 5.0% by mass based on the total mass of the ink. The inkjet ink according to claim 1 or 2 , wherein the hydrophilic main chain has a saponification degree of 77 to 99% and a polymerization degree of 200 to 4000. The inkjet ink according to any one of claims 1 to 3 , wherein a modification rate of the side chain with respect to the hydrophilic main chain is 0.8 mol% or more and 4 mol% or less. The inkjet ink according to any one of claims 1 to 4, characterized in that it contains a water-soluble photopolymerization initiator. An ink-jet ink set comprising two or more ink-jet inks, wherein at least one of the ink-jet inks is the ink-jet ink according to any one of claims 1 to 5 . An ink jet recording method comprising: discharging the ink jet ink according to any one of claims 1 to 5 onto a recording medium, irradiating an active energy ray and then drying the ink. An ink jet recording method comprising: discharging ink jet ink of the ink set for ink jet according to claim 6 onto a recording medium, irradiating with active energy rays, and drying.