JP2019011446A - Aqueous dispersion of water-insoluble dye - Google Patents

Abstract

To provide: an aqueous dispersant of a water-insoluble dye capable of securing an excellent redispersibility capable of suppressing the clogging of a discharge nozzle caused by the solid content in an ink discharge nozzle and storage stability at high temperature; a water-based ink for inkjet recording; an inkjet recording method; and a transfer dyeing method.SOLUTION: There are provided; [1] an aqueous dispersant of a water-insoluble dye containing a water-insoluble dye, a water-insoluble polymer dispersant having an acid value of 80 mgKOH/g or more and 170 mgKOH/g or less and a weight average molecular weight of 100000 or more and water; [2] a water-based ink for inkjet recording containing the aqueous dispersant of a water-insoluble dye and an organic solvent; [3] an inkjet recording method of recording on a sheet-like recording medium using the water-based ink; and [4] a transfer dyeing method in which an intermediate transfer medium recorded by the inkjet recording method and an object to be dyed are overlapped, followed by heating and a dye imparted to the intermediate transfer medium is heated and transferred to an object to be dyed.SELECTED DRAWING: None

Description

  The present invention relates to a water-insoluble dye aqueous dispersion, an aqueous ink for inkjet recording, an inkjet recording method, and a transfer dyeing method.

  The ink jet recording method is a recording method in which ink droplets are directly ejected from fine nozzles and attached to a recording medium to obtain a printed matter on which characters and images are recorded. This method is easily spread at full color and is inexpensive, and has a widespread use because it has a number of advantages in that plain paper can be used as a recording medium and it is non-contact with the recording medium. In recent years, in particular, those using pigments as colorants have become mainstream from the viewpoint of the weather resistance and water resistance of recorded matter.

However, in the case where the recording medium is a fabric, if the colorant is a pigment, the color developability is not sufficient, and thus it is not widely used, and a water-based ink in which a water-insoluble dye is dispersed in water or an aqueous solution containing a water-soluble organic solvent Is often used.
In addition, in the transfer dyeing method in which an intermediate transfer medium is prepared by ink jet printing using a sheet-like recording medium such as transfer paper, and the print surface of the intermediate transfer medium is superposed on a fabric to be heated and transferred, water-insoluble Ink jet recording inks using dyes are used.

By the way, in an aqueous pigment dispersion and an aqueous ink using the same, a functional group having high affinity for water is imparted to the pigment surface, and the pigment is added to an aqueous medium or ink vehicle without a dispersant or using a dispersant. Used in a dispersed manner. However, an ink using a pigment dispersion is difficult to maintain a dispersed state of pigment particles over a long period of time, unlike an ink using a dye that dissolves uniformly in an aqueous medium or an ink vehicle. And pigments may stick.
Accordingly, various proposals have been made to improve the above technical problem.

  In Patent Document 1, a specific proportion of carboxy groups is used for the purpose of obtaining an aqueous pigment dispersion excellent in light resistance, water resistance, solvent resistance, and the like when used in paints, textile printing, printing inks, inkjet inks and the like. An aqueous pigment dispersion in which the solid content weight ratio of the crosslinking agent / carboxy group-containing thermoplastic resin is within a specific range is obtained by dispersing the pigment with the containing thermoplastic resin and then crosslinking the carboxy group-containing thermoplastic resin with a crosslinking agent. It is disclosed. Furthermore, it is described that the thermoplastic resin is preferably neutralized with an organic amine having a boiling point of 200 ° C. or less, and that the neutralization rate is preferably about 100 to 150%.

In addition, as an inkjet ink that has high-quality and stable recording performance and can maintain the storage stability of the ink while increasing the printing density on the surface of the recording medium, Patent Document 2 discloses water, Inkjet containing a sublimation dye, a humectant, a styrene- (meth) acrylic acid copolymer having an acid value of 160 to 250 mg KOH / g and a weight average molecular weight of 8,000 to 20,000, and an acetylene glycol penetrant Sublimation dye inks for use are disclosed.
In Patent Document 3, for the same purpose as Patent Document 2, water, disperse dye, water-soluble organic solvent, styrene having an acid value of 160 to 250 mgKOH / g and a weight average molecular weight of 8,000 to 20,000 An ink for inkjet printing containing a (meth) acrylic acid copolymer and an acetylene glycol penetrant is disclosed.

International Publication No. 1999/052966 International Publication No. 2014/129322 International Publication No. 2014/129323

The aqueous pigment dispersion of Patent Document 1 can bond a polymer dispersing agent for dispersing a pigment three-dimensionally with a crosslinking agent having a plurality of functional groups that react with a carboxy group in one molecule to obtain a strong film. Therefore, the ink stability can be secured to some extent at room temperature. However, when the ink is dried and solidified at the interface with the air at the discharge port of the ink discharge nozzle, the polymer film between the pigments adheres and adheres to each other, and is not redispersed even when new ink is supplied to the discharge nozzle. For this reason, the discharge nozzles may become clogged, and there may be a problem with the discharge properties when resuming printing. In addition, the aqueous pigment dispersion of Patent Document 1 cannot ensure the storage stability of an ink when an ink containing an ink vehicle such as an organic solvent is stored for a long period of time at a high temperature, and requires high reliability. Not satisfied.
In Patent Documents 2 and 3, the acid value of the polymer in which the pigment is dispersed is specified, but since it does not have a three-dimensional cross-linked polymer film, the storage stability of the ink at room temperature can be ensured to some extent. The harsher conditions are still inadequate and not satisfactory.
The present invention provides a water-insoluble dye aqueous dispersion capable of suppressing clogging of a discharge nozzle due to a solid content in an ink discharge nozzle, and a water-insoluble dye aqueous dispersion capable of ensuring storage stability at a high temperature, an aqueous ink for inkjet recording, and an inkjet It is an object of the present invention to provide a recording method and a transfer dyeing method.

  The present inventors can maintain a fluid state in an environment where an ink vehicle is present, such as an ink discharge nozzle portion, while being a strong film in an environment where there is no ink vehicle in contact with the recording medium surface, such as during printing. We aimed to obtain the performance that can form. And it discovered that the said subject could be solved by using a water-insoluble dye and the water-insoluble polymer dispersing agent which has an acid value of a specific range and whose weight average molecular weight is 100,000 or more.

That is, the present invention provides the following [1] to [4].
[1] A water-insoluble dye, a water-insoluble dye dispersant having an acid value of 80 mgKOH / g or more and 170 mgKOH / g or less and a weight average molecular weight of 100,000 or more, and water.
[2] A water-based ink for ink-jet recording comprising the water-insoluble dye aqueous dispersion described in [1] and an organic solvent.
[3] An ink jet recording method for recording on a sheet-like recording medium using the water-based ink according to [2].
[4] The intermediate transfer medium recorded by the ink jet recording method described in [3] above and the object to be dyed are overlaid and heated, and the dye applied to the intermediate transfer medium is sublimated and transferred to the object to be dyed. , Transfer dyeing method.

ADVANTAGE OF THE INVENTION According to this invention, the water-insoluble dye aqueous dispersion which can ensure the outstanding redispersibility which can suppress the clogging of the discharge nozzle by solid content in an ink discharge nozzle, and the storage stability under high temperature, The aqueous ink for inkjet recording Ink jet recording methods and transfer dyeing methods can be provided.
In the present specification, “redispersion” means that a water-insoluble dye or polymer solid produced by volatilization of a volatile component in an ink vehicle is redissolved or redispersed in the ink. When the redispersibility is poor, there is a possibility that, for example, ejection failure due to clogging of the ink ejection nozzles or maintenance problems due to blockage of the ink flow path may occur.

[Water-insoluble dye aqueous dispersion]
The water-insoluble dye aqueous dispersion of the present invention (hereinafter also simply referred to as “dye water dispersion”) has a water-insoluble dye, an acid value of 80 mgKOH / g or more and 170 mgKOH / g or less, and a weight average molecular weight of 100,000 or more. A water-insoluble polymer dispersant (hereinafter, also simply referred to as “polymer dispersant”) and water are contained.
The “water dispersion” means that water accounts for the largest proportion in the dispersion.
The dye aqueous dispersion of the present invention is excellent in storage stability and can be used to obtain a good printed matter. Therefore, the dye aqueous dispersion can be suitably used as a dye aqueous dispersion for flexographic ink, gravure printing ink, or inkjet ink. And can be suitably used as a dye aqueous dispersion for transfer dyeing.
The water-based ink using the dye aqueous dispersion of the present invention is preferably used as a water-based ink for ink jet recording because it is excellent in redispersibility in the ink jet recording system.
In the inkjet printing using the aqueous ink of the present invention, the aqueous ink can be introduced into an inkjet printer by an ordinary method to perform inkjet printing from the inkjet recording head to the sheet-like recording medium. The printed surface can be superimposed on the object to be dyed and heated, and the water-insoluble dye applied to the intermediate transfer medium can be sublimated and transferred to the object to be dyed to obtain a fabric as a product.

The aqueous dye dispersion and water-based ink of the present invention are easy to redisperse even when the volatile component is volatilized at the ink discharge nozzle and the solid content concentration is increased. Also, it has high storage stability that can maintain the performance immediately after production. The reason is not clear, but it is thought as follows.
Since the polymer dispersant used in the present invention is a relatively high molecular weight material having a weight average molecular weight of 100,000 or more, it is difficult to desorb from the water-insoluble dye. Therefore, the high temperature of the dye water dispersion and the water-based ink using the same. It is thought that the storage stability below increases.
In addition, since the acid value of the polymer dispersant is 80 mgKOH / g or more and 170 mgKOH / g or less, strong charge repulsion is obtained, and the dispersion stability of the water-insoluble dye is improved. Even when solidified to form a solid, it is considered that the redispersibility of the solid in ink is excellent.
Furthermore, when the polymer dispersant has a crosslinked structure, the polymer film becomes stronger and the storage stability is further improved, and at least a part of the carboxy groups in the water-insoluble polymer constituting the polymer dispersant is an alkali metal compound. When neutralized with, it is considered that stronger charge repulsion is obtained, the dispersion stability of the water-insoluble dye is enhanced, and the redispersibility is further improved.

<Water-insoluble dye>
The water-insoluble dye used in the present invention refers to a dye that is insoluble or hardly soluble in water, and includes a disperse dye and an oil-soluble dye. The disperse dye refers to a dye that does not have a sulfonic acid group and a carboxy group, which are water-soluble groups in the molecule, and is used for dyeing by dispersing a fine powder of the dye in water. The oil-soluble dye is a dye used for dyeing after being dissolved in a solvent.
Examples of disperse dyes include C.I. I. Disperse Yellow, C.I. I. Disperse Orange, C.I. I. Disperse Brown, C.I. I. Disperse Red, C.I. I. Disperse Violet, C.I. I. Disperse Blue, C.I. I. Various product numbers such as Disperse Green are listed.
Examples of oil-soluble dyes include C.I. I. Solvent Yellow, C.I. I. Solvent Orange, C.I. I. Bat Red, C.I. I. Solvent Red, C.I. I. Solvent Violet, C.I. I. Solvent Blue, C.I. I. Various product numbers such as Solvent Black are listed.
In the present invention, water-insoluble dyes obtained by water-insolubilizing various water-soluble dyes can also be used. As a method for insolubilizing the water-soluble dye, a method of forming an ion complex such as binding a cationic surfactant to an anionic dye is preferable.

Among the above-mentioned disperse dyes and oil-soluble dyes, sublimable dyes are preferred from the viewpoint of efficiently sublimating and transferring water-insoluble dyes to improve dyeability.
Here, the “sublimable dye” means a dye that can be sublimated by heating and diffused and fixed between fibers constituting the fabric.
Examples of disperse dyes include C.I. I. Disperse Yellow, C.I. I. Disperse Orange, C.I. I. Disperse Brown, C.I. I. Disperse Red, C.I. I. Disperse Violet, C.I. I. Disperse Blue, C.I. I. Disperse green and the like.
C. I. Disperse Yellow includes C.I. I. Disperse Yellow 3, 4, 4, 7, 8, 23, 31, 33, 39, 42, 51, 54, 60, 61, 64, 65, 71, 79, 82, 83, 86, 93, 98, 99, 100, 114, 119, 122, 124, 126, 160, 163, 165 180, 183, 184: 1, 186, 198, 199, 200, 201, 211, 224, 237, and the like.
C. I. Disperse Orange includes C.I. I. Disperse Orange 1, 1: 1, 5, 7, 13, 13, 23, 25, 25: 1, 29, 30, 31: 1, 32, 33, 38, 42, 44, 45, 49, 53, 54, 55, 56, 61, 62, 63, 66, 71, 73, 76, 80 86, 96, 118, 119, 155, 163, 288 and the like.
C. I. Disperse Brown includes C.I. I. Disperse Brown 2, 27 and the like.

C. I. Disperse Red includes C.I. I. Disperse Red 1, 4, 4, 5, 11, 11, 12, 13, 15, 17, 22, 31, 32, 33, 34, 35, 36, 50, 52, 53, 54, 55, 55: 1, 56, 58, 59, 60, 65, 70, 72, 73, 75, 76, 80, 84, 86, 88, 91, 92, 93, 99, 111, 113, 126, 127, 131, 134, 135, 143, 145 146, 152, 153, 154, 158, 158, 159, 164, 167: 1, 177, 179, 181, 190, 190: 1, 191 and 192, 204, 205, 206, 207, 221, 224, 225, 227, 23 9, 240, 258, 277, 278, 283, 302, 311, 323, 328, 343, 348, 356, 359, 362, 364, etc. .
C. I. Disperse Violet includes C.I. I. Disperse Violet 8, 17, 23, 26, 27, 28, 29, 33, 35, 36, 48, 56, 57, 77, 97, etc. .

C. I. Disperse Blue includes C.I. I. Disperse Blue 14, 19, 19, 20, 26: 1, 27, 28, 35, 54, 55, 56, 58, 60, 61, 62, 64, 64: 1, 72, 72: 1, 73, 77, 79, 79: 1, 81, 81: 1, 85, 87, 90, 91, etc. 92, 94, 95, 97, 98, 99, 103, 104, 105, 106, 108, 113, 128, 131, 141, 143, 145, 148, 149, 154, 158, 165, 165, 165: 1, 165: 2, 176, 181, 183, 183: 1, 185, 186, 187, 193 194, 195, 197, 198, 201, 205, 207, 211 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 257, 266, 267, 281, 284, 287, 291, 291, 291: 1, 301, 334, 341, 353, 354, 358, 359, 359, 360, 364, 365, 366, 367, 368 and the like.
C. I. Disperse Green includes C.I. I. Disperse Green 6: 1, 9 and so on.

  Examples of oil-soluble dyes include C.I. I. Solvent Yellow 14, 16, 29, 33, 56, 82, 93, 114, 160, 163, C.I. I. Solvent Orange 2, 60, 67; C.I. I. Bat Red 41, C.I. I. Solvent Red 1, 3, 8, 18, 24, 27, 43, 51, 72, 73, 111, 115, 146, 155, C.I. I. Solvent Violet 3, 13 and 31, C.I. I. Solvent Blue 2, 11, 35, 36, 59, 63, 70, 83, 97, 104, 105, 111, C.I. I. Solvent Black 3, 7, 27, 29, 34 and the like.

Among the above water-insoluble dyes, C.I. I. Disperse Yellow 51, 54, 60, 64, 65, 71, 82, C.I. I. Disperse Orange 5, 7, 7, 20, 23, 25, 288, C.I. I. Disperse Red 4, Same 11, 22, 50, 53, 55, 59, 60, 146, 239, 240, 302, 364, C.I. I. Disperse Blue 14, 28, 56, 72, 359, 360, 366, and C.I. I. One or more sublimable disperse dyes selected from Disperse Violet 27 and 28; I. Solvent Yellow 16, 33, 93, 114C. I. Solvent Orange 60, 67, C.I. I. Solvent Red 111, 146, 155, C.I. I. Solvent violet 31, and C.I. I. One or more sublimable dyes selected from Solvent Blue 35, 36, 59, 63, 83, 97, 104, 105, 111 Are preferred, and C.I. I. Disperse Yellow 54, 82, C.I. I. Disperse Orange 25, C.I. I. Disperse Red 60, C.I. I. Disperse Blue 72, 359 and C.I. I. One or more sublimable dyes selected from Disperse Violet 28 are more preferred. I. One or more sublimable dyes selected from Disperse Yellow 54 and Disperse Red 60 are more preferable.
Said water-insoluble dye can be used individually or in combination of 2 or more types.

In the present invention, the water-insoluble dye is a dye dispersed with a water-insoluble polymer dispersant or a water-insoluble polymer dispersant containing a dye, that is, a water-insoluble polymer containing a dye. Contained as particles.
A water-insoluble dye is a water-insoluble dye containing water-insoluble dye from the viewpoint of suppressing the solidification of the water-insoluble dye and polymer in the ink discharge nozzle and improving the storage stability and redispersibility at high temperatures while maintaining water resistance. It is preferably contained as insoluble polymer particles (hereinafter also referred to as “dye-containing polymer particles”), and further crosslinked to form water-insoluble polymer particles containing water-insoluble dye (hereinafter referred to as “dye-containing crosslinked polymer particles”). It is more preferable that it is contained as “

<Polymer dispersant>
The polymer dispersant used in the present invention comprises a water-insoluble polymer having an acid value of 80 mgKOH / g or more and 170 mgKOH / g or less and a weight average molecular weight of 100,000 or more.
In the present invention, when a Tyndall phenomenon is observed by observation with laser light or ordinary light for an aqueous dispersion of an unneutralized or neutralized polymer, or cumulant analysis is performed using the laser particle analysis system shown in the examples. When the average particle diameter is observed, if any of the cases is satisfied, it is determined as “water-insoluble”.
Examples of the polymer dispersant include one or more selected from polyester, polyurethane, and vinyl polymer. From the viewpoint of improving the storage stability of the dye aqueous dispersion and the water-based ink, the vinyl compound, the vinylidene compound, and the vinylene. A vinyl polymer obtained by addition polymerization of one or more vinyl monomers selected from compounds is preferred. These polymers may have a crosslinked structure. The polymer dispersant is an acrylate having a structural unit derived from one or more carboxy group-containing vinyl monomers selected from acrylic acid and methacrylic acid, and an alkyl group having 1 to 22 carbon atoms or an aryl group having 6 to 22 carbon atoms. A vinyl polymer containing a structural unit derived from at least one hydrophobic monomer selected from a monomer, a methacrylate monomer, and an aromatic group-containing monomer is more preferable.

The acid value of the polymer dispersant is preferably derived from a carboxy group, but if the acid value is 80 mgKOH / g or more, the water insolubility of the polymer dispersant can be sufficiently increased, and adsorption to the water-insoluble dye can be improved. It becomes solid and can improve storage stability. If the acid value is 170 mgKOH / g or less, the polymer dispersant is sufficiently hydrophobic and can be strongly adsorbed to the water-insoluble dye, and the amount of carboxy anion present in the dye aqueous dispersion is also sufficient. Can suppress aggregation.
The acid value of the polymer dispersant is preferably 85 mgKOH / g or more, more preferably 90 mgKOH / g or more, still more preferably 105 mgKOH / g or more, still more preferably 110 mgKOH / g or more, and preferably 160 mgKOH / g or less. More preferably, it is 155 mgKOH / g or less, More preferably, it is 150 mgKOH / g or less, More preferably, it is 145 mgKOH / g or less.
The acid value of the polymer can be measured by the method described in the examples. Moreover, it is computable from the mass ratio of the monomer to comprise.

The weight average molecular weight of the polymer dispersant is 100,000 or more, preferably 110,000 or more, more preferably 120,000 or more, more preferably 130,000 or more, and preferably 450,000 or less, more Preferably it is 400,000 or less, More preferably, it is 350,000 or less, More preferably, it is 300,000 or less. When the molecular weight of the polymer dispersant is in the above range, the adsorptive power to the water-insoluble dye is sufficient, and dispersion stability can be expressed.
In addition, the measurement of a weight average molecular weight can be performed by the method as described in an Example.

The polymer dispersant used in the present invention is preferably prepared from a polymer having a carboxy group, and is a water-insoluble polymer (A) having a carboxy group having an acid value of 200 mgKOH / g or more and 320 mgKOH / g or less. It has a crosslinked structure obtained by reacting with a polyfunctional epoxy compound, and at least a part of the carboxy group of the polymer (A) is neutralized with an alkali metal compound, and the acid value and neutralization degree of the polymer (A) And the degree of crosslinking preferably satisfy the following condition 1.
Condition 1: The value of [(100−degree of neutralization−degree of crosslinking) / 100] × (acid value of polymer (A)) is from −30 mgKOH / g to 130 mgKOH / g.
Here, the degree of neutralization is the percentage (mol%) of “number of molar equivalents of alkali metal compound / number of molar equivalents of carboxy group of polymer (A)”, and the degree of crosslinking is “mol of epoxy group of water-insoluble polyfunctional epoxy compound”. It is a percentage ratio (mol%) of “the number of equivalents / the number of molar equivalents of carboxy groups of the polymer (A)”.
In the present invention, the use of an alkali metal compound as a neutralizing agent for the carboxy group increases the charge repulsive force developed after neutralization, and when the dye aqueous dispersion and aqueous ink are stored at high temperatures for a long period of time. It is thought that the occurrence of thickening and aggregation is suppressed, and the storage stability is further improved.

The dye-containing crosslinked polymer particles used in the present invention are preferably water in a state where at least a part of the polymer (A) having a carboxy group having an acid value of 200 mgKOH / g or more and 320 mgKOH / g or less is neutralized with an alkali metal compound. It is preferably formed in an aqueous medium by dispersing the insoluble dye in the aqueous medium and then crosslinking with the water-insoluble polyfunctional epoxy compound. In this case, the polymer dispersant is not isolated, but the relationship between the monomer composition of the polymer (A), the molecular weight, the type and amount of the alkali metal compound, and the type and amount of the water-insoluble polyfunctional epoxy compound, as described later. That state can be expressed as Condition 1.
In addition, by crosslinking the polymer (A), as described above, the weight average molecular weight of the polymer dispersant becomes 100,000 or more.

(Polymer (A))
The polymer (A) for preparing the polymer dispersant has a function as a dye dispersant that exhibits a dispersing action of a water-insoluble dye and a function as a fixing agent to a recording medium.
As the polymer (A), both a water-soluble polymer and a water-insoluble polymer can be used. However, the polymer (A) may be water-insoluble even after neutralization of a part of the carboxy group in an unneutralized state. preferable.
The acid value of the polymer (A) which is the starting material of the polymer dispersant is derived from the carboxy group, but is preferably 200 mgKOH / g or more, more preferably 220 mgKOH / g or more, and preferably 320 mgKOH / g or less, more Preferably it is 300 mgKOH / g or less, More preferably, it is 270 mgKOH / g or less. When the acid value is in the above range, the amount of the carboxy group and the neutralized carboxy group is sufficient, and the dispersion stability of the water-insoluble dye is ensured. It is also preferable from the viewpoint of the balance between the affinity between the polymer dispersant and the aqueous medium and the interaction between the polymer dispersant and the water-insoluble dye.
The acid value of the polymer (A) can be measured by the method described in the examples. Moreover, it is computable from the mass ratio of the monomer to comprise.

Examples of the polymer (A) for preparing the polymer dispersant used in the present invention include one or more selected from polyesters, polyurethanes, and vinyl polymers, and the storage stability of the dye aqueous dispersion and the water-based ink. From the viewpoint of improving the viscosity, a vinyl polymer obtained by addition polymerization of at least one vinyl monomer selected from vinyl compounds, vinylidene compounds, and vinylene compounds is preferable.
Examples of the water-insoluble polymer used as the polymer (A) include (a) a carboxy group-containing vinyl monomer (hereinafter also referred to as “(a) component”) and (b) a hydrophobic vinyl monomer (hereinafter referred to as “(b) component”). And a vinyl polymer obtained by copolymerizing a vinyl monomer mixture (hereinafter also simply referred to as “monomer mixture”). This vinyl polymer has a structural unit derived from the component (a) and a structural unit derived from the component (b). This vinyl polymer is further derived from a structural unit derived from (c) a macromonomer (hereinafter also referred to as “(c) component”) or (d) a nonionic monomer (hereinafter also referred to as “(d) component”). A structural unit can be contained.

[(A) Carboxy group-containing vinyl monomer]
(A) The carboxy group-containing vinyl monomer is used as a monomer component of the polymer (A) from the viewpoint of improving the dispersion stability of the dye-containing polymer particles in the aqueous dispersion and aqueous ink. As the carboxy group-containing vinyl monomer, a carboxylic acid monomer is used.
Examples of the carboxylic acid monomer include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid, 2-methacryloyloxymethyl succinic acid, and the like, but one kind selected from acrylic acid and methacrylic acid The above is preferable.

[(B) Hydrophobic vinyl monomer]
(B) The hydrophobic vinyl monomer is used as a monomer component of the polymer (A) from the viewpoint of improving the dispersion stability of the dye-containing polymer particles in the aqueous dispersion and aqueous ink. Examples of the hydrophobic vinyl monomer include alkyl (meth) acrylates having an alkyl group having 1 to 22 carbon atoms or an aryl group having 6 to 22 carbon atoms, and aromatic group-containing monomers.
As the alkyl (meth) acrylic acid ester, those having an alkyl group having 1 to 22 carbon atoms, preferably 6 to 18 carbon atoms are preferable. For example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) Acrylate, butyl (meth) acrylate, amyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) Acrylate, isopropyl (meth) acrylate, isobutyl (meth) acrylate, tertiary butyl (meth) acrylate, isoamyl (meth) acrylate, isooctyl (meth) acrylate, isodecyl (meth) acrylate , Isododecyl (meth) acrylate, isostearyl (meth) acrylate.
The “(meth) acrylate” means one or more selected from acrylate and methacrylate. “(Meta)” in the following is also synonymous.

As the aromatic group-containing monomer, a vinyl monomer having an aromatic group having 6 to 22 carbon atoms, which may have a substituent containing a hetero atom, is preferable, and a styrene monomer or an aromatic group-containing (meth) acrylate. Is more preferable.
As the styrene monomer, styrene, α-methylstyrene, vinyltoluene, and divinylbenzene are preferable, and styrene and α-methylstyrene are more preferable.
Moreover, as an aromatic group containing (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, etc. are preferable, and benzyl (meth) acrylate is more preferable.
(B) 2 or more types of said monomers may be used for a hydrophobic monomer, and a styrene-type monomer and an aromatic group containing (meth) acrylic acid ester may be used together.

[(C) Macromonomer]
(C) The macromonomer is a compound having a polymerizable functional group at one end and a number average molecular weight of 500 or more and 100,000 or less, and the viewpoint of improving the dispersion stability of the dye-containing polymer particles in the aqueous dispersion and aqueous ink. Therefore, it is preferably used as a monomer component of the polymer (A). The polymerizable functional group present at one end is preferably an acryloyloxy group or a methacryloyloxy group, and more preferably a methacryloyloxy group.
(C) The number average molecular weight of the macromonomer is preferably 1,000 or more and 10,000 or less. The number average molecular weight is measured using polystyrene as a standard substance by gel permeation chromatography using chloroform containing 1 mmol / L dodecyldimethylamine as a solvent.
(C) The macromonomer is preferably an aromatic group-containing monomer-based macromonomer or a silicone-based macromonomer from the viewpoint of improving the dispersion stability of the dye-containing polymer particles in an aqueous dispersion and an aqueous ink. Monomeric macromonomers are more preferred.
Examples of the aromatic group-containing monomer constituting the aromatic group-containing monomer-based macromonomer include the aromatic group-containing monomers described in the above (b) hydrophobic monomer, styrene and benzyl (meth) acrylate are preferred, and styrene is preferred. More preferred.
Specific examples of the styrenic macromonomer include AS-6 (S), AN-6 (S), HS-6 (S) (trade name of Toagosei Co., Ltd.), and the like.
Examples of the silicone macromonomer include organopolysiloxane having a polymerizable functional group at one end.

[(D) Nonionic monomer]
In the polymer (A), it is preferable to further use (d) a nonionic monomer as a monomer component from the viewpoint of improving the dispersion stability of the dye-containing polymer particles in the aqueous dispersion and aqueous ink.
(D) As a nonionic monomer, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, polypropylene glycol (n = 2 to 30, n represents the average number of added moles of an oxyalkylene group. Same) (meth) acrylate, polyethylene glycol (n = 2 to 30) (meth) acrylate and other polyalkylene glycol (meth) acrylate, methoxy polyethylene glycol (n = 1 to 30) (meth) acrylate and other alkoxypolyalkylene glycol (Meth) acrylate, phenoxy (ethylene glycol / propylene glycol copolymer) (n = 1 to 30, ethylene glycol therein: n = 1 to 29) (meth) acrylate, and the like. Among these, polypropylene glycol (n = 2 to 30) (meth) acrylate and phenoxy (ethylene glycol / propylene glycol copolymer) (meth) acrylate are preferable, and polypropylene glycol (n = 2 to 30) (meth) acrylate is preferable. More preferred.

Specific examples of the commercially available component (d) include NK Esters M-20G, 40G, 90G, and 230G from Shin-Nakamura Chemical Co., Ltd., Bremer PE-90 from NOF Corporation, 200, 350, etc., PME-100, 200, 400, etc., PP-500, 800, 1000, etc., AP-150, 400, 550, 50PEP-300, 50POEP-800B, 43PAPE-600B Etc.
The components (a) to (d) can be used alone or in admixture of two or more.
As described above, the polymer (A) used in the present invention is a structural unit derived from one or more (a) carboxy group-containing vinyl monomers selected from acrylic acid and methacrylic acid, an acrylate monomer, a methacrylate monomer, and an aromatic group. It is preferably a water-insoluble polymer containing one or more kinds of structural units derived from (b) a hydrophobic vinyl monomer selected from the containing monomers, and (c) a structural unit derived from a macromonomer, and (d) a nonionic monomer. A water-insoluble polymer containing a structural unit derived from is more preferable.

(Content of each component or structural unit in the monomer mixture or polymer)
The content of the component (a) is preferably 20% by mass or more, more preferably 25% by mass or more, still more preferably 30% by mass or more, and preferably 75% by mass or less, more preferably 60% by mass or less. More preferably, it is 55% by mass or less, and still more preferably 50% by mass or less.
The content of the component (b) is preferably 15% by mass or more, more preferably 20% by mass or more, still more preferably 25% by mass or more, and preferably 80% by mass or less, more preferably 75% by mass or less. More preferably, it is 70 mass% or less.
When the component (c) is contained, the content of the component (c) is preferably 3% by mass or more, more preferably 5% by mass or more, still more preferably 8% by mass or more, and preferably 30% by mass. Hereinafter, it is more preferably 25% by mass or less, and further preferably 20% by mass or less.
When the component (d) is contained, the content of the component (d) is preferably 5% by mass or more, more preferably 10% by mass or more, still more preferably 15% by mass or more, and preferably 40% by mass. Hereinafter, it is more preferably 35% by mass or less, and further preferably 30% by mass or less.

The mass ratio of [component (a) / component (b)] is preferably 0.3 or more, more preferably 0.35 or more, still more preferably 0.40 or more, and preferably 2.0 or less, More preferably, it is 1.5 or less, More preferably, it is 1.2 or less.
When the component (c) is contained, the mass ratio of [(a) component / [(b) component + (c) component]] is preferably 0.1 or more, more preferably 0.3 or more, and further Preferably it is 0.5 or more, and preferably 2.0 or less, more preferably 1.7 or less, and still more preferably 1.5 or less.

(Production of polymer (A))
The polymer (A) is produced by copolymerizing the monomer mixture by a known polymerization method such as a bulk polymerization method, a solution polymerization method, a suspension polymerization method, or an emulsion polymerization method. Among these polymerization methods, the solution polymerization method is preferable.
Although there is no restriction | limiting in particular in the solvent used by a solution polymerization method, A polar organic solvent is preferable. When the polar organic solvent is miscible with water, it can be used by mixing with water. Examples of the polar organic solvent include aliphatic alcohols having 1 to 3 carbon atoms, ketones having 3 to 5 carbon atoms, ethers, esters such as ethyl acetate, and the like. Among these, methanol, ethanol, acetone, methyl ethyl ketone, or a mixed solvent of one or more of these and water, and methyl ethyl ketone or a mixed solvent of water and water are preferable.
In the polymerization, a polymerization initiator or a polymerization chain transfer agent can be used.
As polymerization initiators, azo compounds such as 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), t-butylperoxyoctate, benzoyl peroxide, etc. Known radical polymerization initiators such as organic peroxides can be used. The amount of the radical polymerization initiator is preferably 0.001 to 5 mol, more preferably 0.01 to 2 mol, per mol of the monomer mixture.
As the polymerization chain transfer agent, known chain transfer agents such as mercaptans such as octyl mercaptan and 2-mercaptoethanol, and thiuram disulfides can be used.
Moreover, there is no restriction | limiting in the pattern of the polymerization monomer, and any polymerization pattern such as random, block, or graft may be used.

Preferred polymerization conditions vary depending on the type of polymerization initiator, monomer, solvent, etc. used, but usually the polymerization temperature is preferably 30 ° C. or higher, more preferably 50 ° C. or higher, and preferably 95 ° C. or lower. More than 80 ° C. The polymerization time is preferably 1 hour or longer, more preferably 2 hours or longer, and preferably 20 hours or shorter, more preferably 10 hours or shorter. The polymerization atmosphere is preferably a nitrogen gas atmosphere or an inert gas atmosphere such as argon.
After completion of the polymerization reaction, the produced polymer can be isolated from the reaction solution by a known method such as reprecipitation or solvent distillation. The obtained polymer can be purified by removing unreacted monomers and the like by reprecipitation, membrane separation, chromatographic method, extraction method and the like.
In the present invention, as a method for dispersing a water-insoluble dye using a polymer dispersant, any known method can be used, but an aqueous dispersion of dye-containing polymer particles described later is preferable. From the viewpoint of improving the productivity of the aqueous dispersion of the dye-containing polymer particles, the organic solvent contained in the polymer is used as it is as the organic solvent used in Step I described later without removing the solvent used in the polymerization reaction. A) It is preferably used as a solution.
From the viewpoint of improving the productivity of the aqueous dispersion of the dye-containing polymer particles, the solid content concentration of the polymer (A) solution is preferably 30% by mass or more, more preferably 40% by mass or more, and preferably 70%. It is not more than mass%, more preferably not more than 65 mass%.

The weight average molecular weight of the polymer (A) for preparing the polymer dispersant used in the present invention is preferably 2,000 or more, more preferably 5,000 or more, and preferably 20,000 or less, more Preferably it is 18,000 or less. When the molecular weight of the polymer is in the above range, the adsorptive power to the water-insoluble dye is sufficient and the dispersion stability can be expressed.
In addition, the measurement of a weight average molecular weight can be performed by the method as described in an Example.

[Production of dye-containing polymer particles]
Crosslinked water-insoluble polymer particles containing a water-insoluble dye (dye-containing crosslinked polymer particles) can be efficiently produced by a method having the following steps I to III as an aqueous dispersion.
Step I: Disperse the polymer (A) having a carboxy group, an organic solvent, a mixture containing an alkali metal compound as a neutralizing agent, a water-insoluble dye, and water (hereinafter also referred to as “dye mixture”) to obtain a dye. Step II: Obtaining a Dispersion of Containing Polymer Particles Step II: Removing the organic solvent from the dispersion obtained in Step I to obtain an aqueous dispersion of dye-containing polymer particles (hereinafter also referred to as “dye water dispersion A”). Step III: The aqueous dye dispersion A obtained in Step II is cross-linked with a water-insoluble polyfunctional epoxy compound, and cross-linked water-insoluble polymer particles containing a water-insoluble dye (dye-containing cross-linked polymer particles) are obtained. Of obtaining dye aqueous dispersion B containing

(Process I)
In Step I, first, the polymer (A) is dissolved in an organic solvent, and further, an alkali metal compound, a water-insoluble dye, water, and, if necessary, a surfactant and the like as a neutralizing agent, are obtained. In addition to mixing, a method of obtaining an oil-in-water dispersion is preferred. The order of mixing the organic solvent solution of the polymer (A), the neutralizing agent, the water-insoluble dye, water, etc. is not particularly limited, but the polymer (A) is dissolved in the organic solvent, and the neutralizing agent, water, water It is preferable to add in the order of insoluble dyes.
Although there is no restriction | limiting in the organic solvent to be used, C1-C3 aliphatic alcohol, ketones, ethers, esters, etc. are preferable, wettability to water-insoluble dye, solubility of water-insoluble polymer, and water-insoluble polymer From the viewpoint of improving the adsorptivity to water-insoluble dyes, ketones having 4 to 8 carbon atoms are more preferred, methyl ethyl ketone and methyl isobutyl ketone are more preferred, and methyl ethyl ketone is even more preferred.
When the polymer (A) is synthesized by a solution polymerization method, the solvent used in the polymerization may be used as it is.

(Neutralization)
At least a part of the carboxy group of the polymer (A) is neutralized with an alkali metal compound. From the viewpoint of handling properties such as reducing skin irritation, the pH of the resulting dye aqueous dispersion and aqueous ink is preferably 5.5 or more, more preferably 6 or more, and from the viewpoint of suppressing corrosion of the member. It is preferably 13 or less, more preferably 12 or less, and still more preferably 11 or less.
An alkali metal compound that is a neutralizing agent is a compound that generates an alkali metal ion in an aqueous medium such as water or aqueous ink. For example, an alkali metal such as lithium hydroxide, sodium hydroxide, potassium hydroxide, or cesium hydroxide. Hydroxides, alkali metal salts of silicic acid such as sodium orthosilicate, sodium metasilicate and sodium sesquisilicate, alkali metal salts of phosphoric acid such as trisodium phosphate, carbonic acid such as disodium carbonate, sodium hydrogen carbonate, dipotassium carbonate And alkali metal salts of boric acid such as sodium borate. Two or more alkali metal compounds may be combined. As an alkali metal compound, an alkali metal hydroxide is preferable, and sodium hydroxide and potassium hydroxide are more preferable. The polymer (A) may be neutralized in advance.
The neutralizing agent is preferably used as an aqueous neutralizing agent solution from the viewpoint of sufficiently and uniformly promoting neutralization. From the above viewpoint, the concentration of the neutralizer aqueous solution is preferably 3% by mass or more, more preferably 10% by mass or more, further preferably 15% by mass or more, more preferably 50% by mass or less, and preferably 25% by mass or less. More preferred.

The degree of neutralization of the carboxy group of the polymer (A) is preferably at least 20 mol%, more preferably from the viewpoint of further improving the storage stability and redispersibility of the obtained dye aqueous dispersion and aqueous ink at high temperatures. It is 25 mol% or more, more preferably 30 mol% or more, and preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 60 mol% or less.
Here, the degree of neutralization is the percentage (mol%) obtained by dividing the number of mole equivalents of the alkali metal compound by the number of mole equivalents of the carboxy group of the polymer (A), that is, “number of mole equivalents of alkali metal compound / polymer (A)”. Is the percentage (mol%) of the "number of mole equivalents of carboxy groups". In the present invention, since the degree of neutralization is calculated from the number of molar equivalents of the alkali metal compound, it exceeds 100 mol% when the alkali metal compound is used in excess.

In Step I, a volatile basic compound can be used in combination with the alkali metal compound. Examples of the volatile basic compound include ammonia, trimethylamine, and triethylamine. Ammonia is preferable from the viewpoint of high volatility.
There is no particular limitation on the amount of the volatile basic compound used, but it is not used at all, or when used, it is 10 mol% or more, preferably 20 mol% or more, more preferably 25 mol% or more, still more preferably 30 mol. % And preferably 100 mol% or less, more preferably 90 mol% or less, still more preferably 80 mol% or less, and still more preferably 75 mol% or less. In addition, only the usage-amount of an alkali metal compound is used for calculation of a neutralization degree, and the usage-amount of a volatile basic compound is not used for calculation of the neutralization degree of this invention.

(Content of each component in the dye mixture)
The content of each component in the dye mixture is as follows from the viewpoint of further improving the storage stability, redispersibility, and productivity of the obtained dye aqueous dispersion at high temperatures.
The content of the water-insoluble dye in Step I in the dye mixture is preferably 5% by mass or more, more preferably 10% by mass or more, still more preferably 12.5% by mass or more, and preferably 35% by mass or less. More preferably, it is 30 mass% or less, More preferably, it is 20 mass% or less.
The content of the polymer (A) in the dye mixture is preferably 1.0% by mass or more, more preferably 2.0% by mass or more, still more preferably 3.0% by mass or more, and preferably 8. It is 0 mass% or less, More preferably, it is 7.0 mass% or less, More preferably, it is 6.0 mass% or less.
The content of the organic solvent in the dye mixture is preferably 5% by mass or more, more preferably 7% by mass or more, still more preferably 10% by mass or more, and preferably 35% by mass or less, more preferably 30% by mass. % Or less, more preferably 25% by mass or less.
The content of the water in the dye mixture is preferably 40% by weight or more, more preferably 45% by weight or more, still more preferably 50% by weight or more, and preferably 85% by weight or less, more preferably 80% by weight. Hereinafter, it is more preferably 75% by mass or less.

  The mass ratio of the water-insoluble dye to the polymer (A) in the dye mixture [water-insoluble dye / polymer (A)] is from the viewpoint of further improving the storage stability and redispersibility of the resulting aqueous dye dispersion at high temperatures. , Preferably 0.5 or more, more preferably 1 or more, still more preferably 1.5 or more, still more preferably 2 or more, and preferably 8 or less, more preferably 7 or less, still more preferably 6 or less, More preferably, it is 5 or less.

(Dispersion treatment of dye mixture)
In step I, the dye mixture is dispersed to obtain a dispersion of dye-containing polymer particles. There is no particular limitation on the dispersion method for obtaining the dispersion. Although the average particle diameter of the water-insoluble dye particles can be atomized only by the main dispersion until the desired particle diameter is reached, preferably the dye mixture is predispersed, and then the main dispersion is performed by further applying shear stress, It is preferable to control the average particle size of the water-insoluble dye particles to a desired particle size.
The temperature in Step I, particularly the temperature in the preliminary dispersion, is preferably 0 ° C. or higher, preferably 40 ° C. or lower, more preferably 30 ° C. or lower, still more preferably 25 ° C. or lower, and the dispersion time is preferably 0. .5 hours or more, more preferably 0.8 hours or more, preferably 30 hours or less, more preferably 10 hours or less, still more preferably 5 hours or less.
When the dye mixture is predispersed, commonly used mixing and stirring devices such as anchor blades and disper blades can be used, and among them, a high-speed stirring and mixing device is preferable.

Examples of means for imparting the shear stress of this dispersion include a kneader such as a roll mill and a kneader, a high-pressure homogenizer such as a microfluidizer (manufactured by Microfluidic), a media-type disperser such as a paint shaker and a bead mill. Examples of commercially available media dispersers include Ultra Apex Mill (manufactured by Kotobuki Industries Co., Ltd.), Picomill (manufactured by Asada Tekko Co., Ltd.), and the like. A plurality of these devices can be combined. Among these, it is preferable to use a high-pressure homogenizer from the viewpoint of reducing the particle size of the water-insoluble dye.
When this dispersion is performed using a high-pressure homogenizer, the water-insoluble dye can be controlled to have a desired particle size by controlling the processing pressure and the number of passes.
From the viewpoint of productivity and economy, the treatment pressure is preferably 60 MPa or more, more preferably 100 MPa or more, still more preferably 130 MPa or more, and preferably 200 MPa or less, more preferably 180 MPa or less.
The number of passes is preferably 3 or more, more preferably 10 or more, and preferably 30 or less, more preferably 25 or less.

(Process II)
In Step II, an aqueous dispersion of dye-containing polymer particles (Dye Water Dispersion A) can be obtained by removing the organic solvent from the dispersion obtained in Step I by a known method. The organic solvent in the obtained dye aqueous dispersion is preferably substantially removed, but may remain as long as the object of the present invention is not impaired. The amount of the residual organic solvent is preferably 0.1% by mass or less, more preferably 0.01% by mass or less.
If necessary, the dispersion can be heated and stirred before the organic solvent is distilled off.
The obtained dye aqueous dispersion A is one in which dye-containing polymer particles are dispersed in a medium containing water as a main medium. Here, the existence form of the dye-containing polymer particles includes a state in which it is adsorbed to a water-insoluble dye, a state in which a water-insoluble dye is contained (a particle form in which a water-insoluble dye is encapsulated (encapsulated), water-insoluble Including a particle form in which a dye is uniformly dispersed). From the viewpoint of the dispersion stability of the water-insoluble dye, the form of the dye-containing polymer particle is preferred in the present invention, and the form of the particle containing the water-insoluble dye and containing the water-insoluble dye in the polymer (A) is more preferred.

The non-volatile component concentration (solid content concentration) of the obtained dye aqueous dispersion A is preferably 10% by mass or more from the viewpoint of improving the dispersion stability of the dye aqueous dispersion and facilitating preparation of the aqueous ink. More preferably, it is 15 mass% or more, Preferably it is 30 mass% or less, More preferably, it is 25 mass% or less.
In addition, the solid content density | concentration of the dye aqueous dispersion A is measured by the method as described in an Example.
The average particle diameter of the dye-containing polymer particles in the dye aqueous dispersion A is preferably 50 nm or more, more preferably 60 nm or more, and still more preferably 70 nm, from the viewpoint of reducing coarse particles and improving the discharge stability of the water-based ink. In addition, it is preferably 200 nm or less, more preferably 160 nm or less, and still more preferably 140 nm or less.
The average particle size of the dye-containing polymer particles is measured by the method described in the examples.

(Process III)
In Step III, from the viewpoint of further improving the storage stability and redispersibility of the obtained dye aqueous dispersion and aqueous ink at high temperatures, the dye aqueous dispersion A obtained in Step II is used as a water-insoluble polyfunctional compound described later. A crosslinking treatment is performed with an epoxy compound (crosslinking agent) to obtain an aqueous dye dispersion B containing crosslinked water-insoluble polymer particles (dye-containing crosslinked polymer particles) containing a water-insoluble dye. In this step, a part of the carboxy group of the polymer (A) constituting the dye-containing polymer particle is crosslinked to form a crosslinked structure in the surface layer portion of the dye-containing polymer particle.
That is, the polymer dispersant according to the present invention is obtained by crosslinking the polymer (A) and the water-insoluble polyfunctional epoxy compound on the surface of the water-insoluble dye, and is contained in the dye-containing polymer particles in the dye water dispersion ( A) becomes a water-insoluble polymer crosslinked by a water-insoluble polyfunctional epoxy compound. Thus, the dye aqueous dispersion of the present invention becomes a dye aqueous dispersion in which a water-insoluble dye is dispersed in an aqueous medium with the water-insoluble polymer dispersant according to the present invention.

<Water-insoluble polyfunctional epoxy compound>
When the water-insoluble polyfunctional epoxy compound (crosslinking agent) used in the present invention is dissolved in 100 g of water at 20 ° C. from the viewpoint of efficiently crosslinking with the carboxy group of the polymer (A) in a medium mainly composed of water. The amount of dissolution is preferably 55 g or less, more preferably 44 g or less, and still more preferably 39 g or less.
Further, the water-insoluble polyfunctional epoxy compound has a water content of preferably 50% by mass or less, more preferably from the viewpoint of further improving the storage stability and redispersibility of the obtained dye aqueous dispersion and aqueous ink at high temperatures. Is 40% by mass or less, more preferably 35% by mass or less.
Here, the water content (mass%) refers to the solubility (mass%) when 10 parts by mass of an epoxy compound is dissolved in 90 parts by mass of water at a room temperature of 25 ° C., more specifically, in the examples. It is measured by the method described.

The water-insoluble polyfunctional epoxy compound is preferably a compound having 2 or more epoxy groups in the molecule, more preferably a compound having a glycidyl ether group, more preferably a polyvalent having 3 to 8 carbon atoms. It is a glycidyl ether compound of alcohol.
The molecular weight of the water-insoluble polyfunctional epoxy compound is preferably 120 or more, more preferably 150 or more, still more preferably 200 or more, from the viewpoint of easy reaction and the storage stability of the resulting crosslinked polymer. Preferably it is 2000 or less, More preferably, it is 1500 or less, More preferably, it is 1000 or less.
The number of epoxy groups of the water-insoluble polyfunctional epoxy compound is 2 or more, preferably 3 or more per molecule, from the viewpoint of efficiently cross-linking with a carboxy group and improving the storage stability of the dye-containing polymer particles, and the like. Preferably it is 6 or less per molecule. Since those having 5 or more epoxy groups in one molecule have poor market availability, 3 or more and 4 or less are particularly preferable from the viewpoint of achieving both reactivity and economy.

Specific examples of the water-insoluble polyfunctional epoxy compound include polypropylene glycol diglycidyl ether, glycerin polyglycidyl ether, glycerol polyglycidyl ether, polyglycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether, sorbitol polyglycidyl ether, pentaerythritol polyglycidyl. And polyglycidyl ethers such as ether, resorcinol diglycidyl ether, neopentyl glycol diglycidyl ether, hydrogenated bisphenol A type diglycidyl ether, and the like.
Among these, one or more selected from polypropylene glycol diglycidyl ether (water solubility 31%), trimethylolpropane polyglycidyl ether (water solubility 27%), and pentaerythritol polyglycidyl ether (water solubility less than 20%) are preferable. .

(Preferred embodiment)
In a preferred embodiment of the present invention, a water-insoluble dye is dispersed by neutralizing a part of the carboxy group of the polymer (A) having a carboxy group having an acid value of 200 mgKOH / g or more and 320 mgKOH / g or less with an alkali metal compound. After obtaining the dye aqueous dispersion A, the polymer (A) is further reacted with a part of the carboxy group of the polymer (A) with a water-insoluble polyfunctional epoxy compound to form a crosslinked structure. A dye aqueous dispersion B in which a water-insoluble dye is dispersed in an aqueous medium with an agent is prepared. At that time, from the viewpoint of further improving the storage stability and redispersibility of the dye aqueous dispersion B and water-based ink obtained at high temperatures, the alkali metal compound and the water-insoluble polyfunctional epoxy compound are satisfied in an amount satisfying the following condition 1. Is preferably used.

[Condition 1]
Condition 1 is that the value of [(100−degree of neutralization−degree of crosslinking) / 100] × [acid value of polymer (A)] is −30 mgKOH / g or more and 130 mgKOH / g or less.
Here, the degree of neutralization is the percentage (mol%) of “number of molar equivalents of alkali metal compound / number of molar equivalents of carboxy group of polymer (A)”, and the degree of crosslinking is “mol of epoxy group of water-insoluble polyfunctional epoxy compound”. It is a percentage ratio (mol%) of “the number of equivalents / the number of molar equivalents of carboxy groups of the polymer (A)”.
Condition 1 indicates the amount of unneutralized carboxy group of the polymer dispersant in the dye dispersion necessary for enhancing the storage stability and redispersibility. The acid value of the polymer (A), the degree of neutralization, Determined by the degree of crosslinking. If the value of Condition 1 is 130 mgKOH / g or less, the charge amount on the surface of the water-insoluble dye is sufficient when the dye dispersion is prepared using the polymer, and the water-insolubility of the polymer dispersant is sufficient. Excellent storage stability can be expressed.
The value of Condition 1 is preferably 100 mgKOH / g or less, more preferably 90 mgKOH / g or less, and still more preferably 80 mgKOH / g or less. At this time, if the value is −30 mgKOH / g or more, excellent storage stability can be exhibited. When the value is less than -30 mgKOH / g, it means that the degree of neutralization is too high or the degree of crosslinking is too high. The amount of carboxy groups to be reduced is too small and the amount of charge becomes insufficient, so that sufficient storage stability cannot be exhibited. The value of Condition 1 is preferably −20 mgKOH / g or more, more preferably −10 mgKOH / g or more, and further preferably −5 mgKOH / g or more.

In a preferred embodiment of the present invention, it is preferable that the following condition 2 is further satisfied.
[Condition 2]
Condition 2 is that the value of [(degree of neutralization) / 100] × [acid value of polymer (A)] is 80 mgKOH / g or more and 180 mgKOH / g or less.
Condition 2 indicates the amount of neutralized carboxy group necessary for enhancing storage stability and redispersibility. In order to enhance the redispersibility of the water-insoluble dye particles in the dye aqueous dispersion, the condition of the neutralization degree is important. If the value of condition 2 is 180 mgKOH / g or less, the amount of carboxy anion present in the dye aqueous dispersion is appropriate and enhances storage stability. If the value of condition 2 is 80 mgKOH / g or more, carboxy anion Is sufficient, charge repulsion is strong, and aggregation of water-insoluble dye particles hardly occurs.
The value of Condition 2 is preferably 90 mgKOH / g or more, more preferably 95 mgKOH / g or more, still more preferably 100 mgKOH / g or more, still more preferably 110 mgKOH / g or more, and preferably 175 mgKOH / g or less, more Preferably it is 170 mgKOH / g or less, More preferably, it is 160 mgKOH / g or less.

(Crosslinking reaction conditions)
Crosslinking of the water-insoluble polyfunctional epoxy compound and the carboxy group of the polymer (polymer (A)) is preferably performed after the water-insoluble dye is dispersed in the polymer (A).
From the same viewpoint as described above, the reaction temperature is preferably 40 ° C. or higher, more preferably 50 ° C. or higher, still more preferably 55 ° C. or higher, still more preferably 60 ° C. or higher, and still more preferably 65 ° C. or higher. And preferably it is 95 degrees C or less, More preferably, it is 90 degrees C or less.
The reaction time is preferably 0.5 hours or more, more preferably 1 hour or more, still more preferably 1.5 hours or more, and even more preferably 3.0 hours or more from the viewpoint of completion of the reaction and economy. And preferably 12 hours or less, more preferably 10 hours or less, still more preferably 8.0 hours or less, and even more preferably 6 hours or less.
The degree of crosslinking of the crosslinked water-insoluble polymer is preferably 5 mol% or more, more preferably 10 mol% or more, still more preferably 20 mol% or more, still more preferably 25 mol% or more, still more preferably 30 mol% or more. And preferably 80 mol% or less, more preferably 75 mol% or less, and still more preferably 70 mol% or less.
The degree of crosslinking is an apparent degree of crosslinking calculated from the acid value of the polymer and the equivalent of the epoxy group of the crosslinking agent. That is, the degree of crosslinking is a percentage (mol%) of “number of molar equivalents of epoxy group of water-insoluble polyfunctional epoxy compound / number of molar equivalents of carboxy group of polymer (A)”.

The average particle diameter of the dye-containing crosslinked polymer particles in the dye aqueous dispersion B is preferably 50 nm or more, more preferably 60 nm or more, and still more preferably, from the viewpoint of reducing coarse particles and improving the discharge stability of water-based ink. It is 70 nm or more, preferably 200 nm or less, more preferably 180 nm or less, still more preferably 160 nm or less, and still more preferably 150 nm or less.
The average particle size of the dye-containing crosslinked polymer particles is measured by the method described in the examples.
The average particle diameter of the dye-containing crosslinked polymer particles in the water-based ink is the same as the average particle diameter in the dye water dispersion B, and the preferred average particle diameter is the average particle diameter in the dye water dispersion. This is the same as the preferred embodiment.

The dye content in the obtained dye aqueous dispersion B is preferably 3% by mass or more, more preferably 8% by mass or more, and still more preferably 10% by mass or more from the viewpoint of improving the printing density at high temperatures. From the viewpoint of further improving the storage stability, it is preferably 30% by mass or less, more preferably 25% by mass or less, and still more preferably 20% by mass or less.
The mass ratio of the water-insoluble dye to the polymer dispersant in the dye aqueous dispersion [water-insoluble dye / polymer dispersant] is preferable from the viewpoint of further improving the storage stability and redispersibility of the dye aqueous dispersion at high temperatures. Is 0.5 or more, more preferably 1 or more, still more preferably 1.5 or more, still more preferably 2 or more, and is preferably 8 or less, more preferably 7 or less, still more preferably 6 or less, and even more. Preferably it is 5 or less.
Moreover, it is preferable that pH of the dye aqueous dispersion B obtained is 8.0 or more. If the pH is 8.0 or more, the dissociation of the anionic group is promoted, and the charge amount of the dye dispersion is sufficient, which can improve the storage stability of the dye dispersion. The pH of the dye aqueous dispersion B is preferably 8.5 or more, and the upper limit thereof is not particularly limited. However, when the pH exceeds 11, the pH of the ink using the dye dispersion becomes too high, and the ink This is unfavorable because it adversely affects the members of printers and printing presses that use. Therefore, the pH of the dye aqueous dispersion B is more preferably 10.5 or less.
Although there is no restriction | limiting in particular in the measuring method of pH, The pH measuring method using a glass electrode is prescribed | regulated to JISZ8802, and this method is preferable from a simple and accurate point. Specifically, it is measured by the method described in the examples.

[Water-based ink for inkjet recording]
The water-based ink for inkjet recording of the present invention contains the water-insoluble dye aqueous dispersion of the present invention and an organic solvent.
The water-based ink of the present invention can be obtained by mixing the dye water dispersion B obtained in Step III, an organic solvent, water, and various additives such as a surfactant, if necessary. .
The water-based ink obtained by the production method of the present invention is a dye-containing polymer particle, preferably a dye-water dispersion containing dye-containing crosslinked polymer particles, and a water-based ink containing an organic solvent and water.
The organic solvent is used from the viewpoint of further improving the storage stability of the water-based ink. The organic solvent used here preferably includes one or more organic solvents having a boiling point of 90 ° C. or higher, and is preferably an organic solvent having a boiling point weighted average value of 250 ° C. or lower. The weighted average value of the boiling point of the organic solvent is preferably 150 ° C. or higher, more preferably 180 ° C. or higher, and preferably 240 ° C. or lower, more preferably 220 ° C. or lower, still more preferably 200 ° C. or lower.
Specific examples of the organic solvent include polyhydric alcohol, polyhydric alcohol alkyl ether, nitrogen-containing heterocyclic compound, amide, amine, sulfur-containing compound and the like. Among these, at least one selected from polyhydric alcohol and polyhydric alcohol alkyl ether is preferable, and is selected from ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, glycerin, trimethylolpropane, and diethylene glycol diethyl ether. 1 or more types are more preferable, and 1 or more types chosen from glycerol, a triethylene glycol, and a trimethylol propane are still more preferable.
Examples of the surfactant include nonionic surfactants, anionic surfactants, amphoteric surfactants, silicone surfactants, and fluorine surfactants. Of these, nonionic surfactants are preferred.

In the method for producing a water-based ink of the present invention, if necessary, various additives such as a viscosity modifier, an antifoaming agent, a preservative, a mildew-proofing agent, and a rust-preventing agent that are usually used in water-based inks are added. Further, a filtration treatment with a filter or the like can be performed.
The content of each component of the water-based ink and the ink physical properties are as follows.

(Content of water-insoluble dye)
From the viewpoint of improving the printing density of the water-based ink, the content of the water-insoluble dye in the water-based ink is preferably 1% by mass or more, more preferably 2% by mass or more, and further preferably 2.5% by mass or more. Further, from the viewpoint of lowering the ink viscosity at the time of solvent volatilization and further improving the storage stability at high temperature, it is preferably 15% by mass or less, more preferably 10% by mass or less, and further preferably 7% by mass or less.
(Total content of water-insoluble dye and polymer dispersant)
The total content of the water-insoluble dye and the polymer dispersant in the water-based ink is preferably 2% by mass or more, more preferably 2.5% by mass or more, still more preferably 3% by mass or more, and still more preferably 3.5%. And preferably 17% by mass or less, more preferably 12% by mass or less, still more preferably 10% by mass or less, still more preferably 8% by mass or less, and even more preferably 7% by mass or less. .
The mass ratio of the water-insoluble dye to the polymer dispersant in the water-based ink [water-insoluble dye / polymer dispersant] is preferably 0.5 from the viewpoint of further improving the storage stability and redispersibility of the water-based ink at high temperatures. Or more, more preferably 1 or more, still more preferably 1.5 or more, still more preferably 2 or more, and preferably 8 or less, more preferably 7 or less, still more preferably 6 or less, even more preferably 5 or less. It is.

(Water-based ink properties)
From the viewpoint of further improving the storage stability of the ink, the viscosity at 32 ° C. of the water-based ink is preferably 2.0 mPa · s or more, more preferably 3.0 mPa · s or more, and further preferably 5.0 mPa · s. S or more, and preferably 12 mPa · s or less, more preferably 9.0 mPa · s or less, and even more preferably 7.0 mPa · s or less.
The pH of the water-based ink is preferably 7.0 or more, more preferably 7.2 or more, and further preferably 7.5 or more, from the viewpoint of further improving the storage stability of the ink. Moreover, from a viewpoint of member tolerance and skin irritation, pH becomes like this. Preferably it is 11.0 or less, More preferably, it is 10.0 or less, More preferably, it is 9.5 or less.

[Inkjet recording method]
In the ink jet recording method of the present invention, the water-based ink for ink jet recording of the present invention is loaded into a known ink jet recording apparatus and ejected as ink droplets onto a sheet-like recording medium to record images such as characters and pictures.
As the ink jet recording apparatus, there are a thermal type and a piezo type, and it is more preferable to use the ink as a piezo type aqueous ink for ink jet recording.
The recording medium that can be used is not particularly limited, but considering application to the sublimation transfer dyeing method, the ink absorbability and drying properties are excellent, and the dye in the ink adhering to the recording medium is absorbed on the surface of the recording medium. It is preferable that the ink does not aggregate and the ink is easily sublimated by heating the back surface of the recording medium. For example, paper having wood pulp as a main component, paper having an ink receiving layer formed on the surface with inorganic fine particles such as silica, etc., and porous resin films made of polyester, polyvinyl chloride, polypropylene, polyethylene, etc. Can be mentioned.

[Transfer dyeing method]
In the transfer dyeing method of the present invention, the intermediate transfer medium recorded by the ink jet recording method of the present invention and the object to be dyed are overlaid and heated, and the dye applied to the intermediate transfer medium is sublimated and transferred to the object to be dyed. To do. Image information such as characters and pictures is recorded on the intermediate transfer medium. By using this intermediate transfer medium, transfer dyeing can be performed on an object to be dyed.
The object to be dyed is not particularly limited, and may be a fabric or a resin film.
When the object to be dyed is a fabric, the fiber constituting the fabric is not particularly limited. For example, plant fibers such as cotton and hemp, animal fibers such as silk, wool, alpaca, Angola, cashmere, and mohair, Recycled fibers such as rayon, cupra, and polynosic, semi-synthetic fibers such as acetate, triacetate, and promix, synthetic fibers such as nylon, polyester, acrylic, polyvinyl chloride, and polyurethane, and blended products using two or more of these fibers Is mentioned. Examples of the resin film that can be used include films of polyester, polyurethane, polyamide film, acrylic, polyvinyl chloride, and the like.
Among these, a fabric is preferable, a synthetic fiber fabric such as nylon, polyester, acrylic, polyvinyl chloride, and polyurethane is preferable, and a polyester fiber fabric is more preferable.

The heating temperature in transfer dyeing is preferably 150 ° C. or higher, more preferably 160 ° C. or higher, still more preferably 170 ° C. or higher, and preferably 220 ° C. or lower, from the viewpoint of color development and productivity of the dyed product. Preferably it is 215 degrees C or less, More preferably, it is 210 degrees C or less. Although depending on the heating temperature, the heating time is preferably 30 seconds or longer, more preferably 45 seconds or longer, and preferably 100 seconds or shorter, more preferably 80 seconds or shorter.
The transfer dyeing can be performed by heating the surface of the intermediate transfer medium to which ink has been applied in a state of being opposed to the object to be dyed at a constant interval, or the intermediate transfer medium and the object to be dyed. It can also be performed by heating in a state where these are in close contact with each other. Among these, from the viewpoint of eliminating the positional deviation between the object to be dyed and the intermediate transfer medium, accurately transferring the dye at a desired position, and reducing the energy required for the transfer and improving the productivity, the intermediate transfer It is preferable to heat the medium and the object to be dyed in close contact with each other.

  In the following preparation examples, production examples, examples and comparative examples, “parts” and “%” are “parts by mass” and “% by mass” unless otherwise specified.

(1) Measurement of weight average molecular weight of polymer The MEK solution of each water-insoluble polymer obtained in Preparation Examples 1 to 9 below was subjected to N, N-dimethylformamide (manufactured by Wako Pure Chemical Industries, Ltd., for high performance liquid chromatography). A sample for measurement was prepared by diluting the polymer solid content to 0.1%. In addition, phosphoric acid (made by Wako Pure Chemical Industries, Ltd., reagent special grade) and lithium bromide (made by Tokyo Chemical Industry Co., Ltd., reagent) were added to N, N-dimethylformamide (same) at 60 mmol / L and 50 mmol / L, respectively. Gel chromatography method [Tosoh Corporation GPC apparatus (HLC-8120GPC), Tosoh Corporation column (TSK-GEL, α-M × 2), flow rate: 1 mL / min], using monodisperse polystyrene having a known molecular weight as a standard substance.

(2) Measurement of weight average molecular weight of polymer dispersant Each water-insoluble dye aqueous dispersion B (solid content: 20 to 21%) obtained in the following Examples 1 to 14 and Comparative Examples 1 to 6 was converted to N, N-dimethylformamide. (Same as above) The filtrate was diluted with a solid content of 0.3% and allowed to stand for 24 hours, and then filtered through an Acrodisc PTFE syringe filter (opening 0.2 μm, 25 mmφ) manufactured by Pall Corporation. A sample for measurement was used.
For the measurement sample, the weight average molecular weight was calculated in the same procedure as in (1) above.

(3) Measurement of average particle diameter of dye-containing polymer particles The measurement was performed by cumulant analysis using a laser particle analysis system “ELSZ-1000” (manufactured by Otsuka Electronics Co., Ltd.). It diluted with water so that a measurement density | concentration might be 5 * 10 < ^-3 > mass% (solid content concentration conversion). The measurement conditions were a temperature of 25 ° C., an incident light / detector angle of 165 °, and an integration count of 100 times. The particle size was defined as the average particle size of the dye-containing polymer particles.

(4) Measurement of acid value of polymer 2 g of the polymer before crosslinking or 2 g of the dye aqueous dispersion after crosslinking was diluted with 50 g of ion-exchanged water, and 3 ml of 0.1N sodium hydroxide solution was added. 0.1N hydrochloric acid was gradually added dropwise thereto, and two inflection points of pH were measured. The number of moles of acid calculated from the difference in the amount of 0.1N hydrochloric acid dropped between the two points corresponds to the number of moles of carboxylic acid in the polymer, and this number of moles was converted to an acid value.

(5) Measurement of solid content concentration of water-insoluble dye aqueous dispersion A 10.0 g of sodium sulfate constant in a desiccator was weighed into a 30 ml polypropylene container (φ = 40 mm, height = 30 mm) About 1.0 g was added and mixed, then accurately weighed and maintained at 105 ° C. for 2 hours to remove volatiles and left in a desiccator for an additional 15 minutes to measure the mass. The mass of the sample after removal of the volatile matter was taken as the solid content and divided by the mass of the added sample to obtain the solid content concentration.

(6) Measurement of water content of epoxy compound Constant temperature at which room temperature was 25 ° C., 90 parts by mass of ion exchange water and 10 parts by mass of crosslinking agent were added to a glass tube (25 mmφ × 250 mmh), and the glass tube was adjusted to a water temperature of 25 ° C. It left still in the tank for 1 hour. Next, the glass tube was vigorously shaken for 1 minute, and then allowed to stand again in a thermostatic bath for 10 minutes. Subsequently, the undissolved material was weighed and the water solubility (mass%) was calculated.

(7) Measurement of pH of water-insoluble dye aqueous dispersion A desktop pH meter “F-71” (manufactured by Horiba, Ltd.) using a pH electrode “6337-10D” (manufactured by Horiba, Ltd.) The pH of the water-insoluble dye dispersion at 20 ° C. was measured.

<Preparation of polymer dispersant>
Preparation Example 1
46 parts of methacrylic acid (manufactured by Wako Pure Chemical Industries, Ltd., reagent), 94 parts of benzyl acrylate (manufactured by Wako Pure Chemical Industries, Ltd., reagent), styrene macromer (manufactured by Toagosei Co., Ltd., trade name: AS-6S, number average) Molecular weight: 6000, solid content concentration 50%) 40 parts (20 parts as solid content), polypropylene glycol monomethacrylate (manufactured by NOF Corporation, trade name: Blemmer PP-800, propylene oxide average added mole number 13, terminal: hydroxyl group ) 40 parts were mixed to prepare a monomer mixture. In a reaction vessel, 20 parts of methyl ethyl ketone (MEK), 0.3 part of 2-mercaptoethanol (polymerization chain transfer agent) and 10% of the monomer mixture were mixed and sufficiently substituted with nitrogen gas.
Meanwhile, in the dropping funnel, the remaining 90% of the monomer mixture, 0.27 part of the polymerization chain transfer agent, 60 parts of MEK, and an azo radical polymerization initiator (trade name: V-65, manufactured by Wako Pure Chemical Industries, Ltd.) , 2,2′-azobis (2,4-dimethylvaleronitrile)) 2.2 parts of a mixed solution, and in a nitrogen atmosphere, the monomer mixed solution in the reaction vessel was stirred and heated to 65 ° C., The mixed solution in the dropping funnel was dropped over 3 hours. After 2 hours at 65 ° C. from the end of the dropwise addition, a solution in which 0.3 part of the polymerization initiator was dissolved in 5 parts of MEK was added, and further aged at 65 ° C. for 2 hours and 70 ° C. for 2 hours. A polymer solution (a) (weight average molecular weight of the polymer: 11000, acid value of 150 mgKOH / g) was obtained.

Preparation Examples 2-4
In Preparation Example 1, a water-insoluble polymer solution having a carboxy group was prepared in the same procedure as in Preparation Example 1 except that the amount of methacrylic acid, benzyl acrylate, styrene macromer, and Blenmer PP-800 was changed as shown in Table 1. b) to (d) were obtained. The results are shown in Table 1.

Preparation Example 5
Acrylic acid (Wako Pure Chemical Industries, Ltd., reagent) 38.5 parts, Styrene (Wako Pure Chemical Industries, Ltd. reagent) 152.5 parts, α-methylstyrene (Wako Pure Chemical Industries, Ltd., reagent) 9 Parts were mixed to prepare a monomer mixture. In a reaction vessel, 20 parts of MEK, 0.3 part of 2-mercaptoethanol (polymerization chain transfer agent) and 10% of the monomer mixture were mixed and sufficiently replaced with nitrogen gas.
On the other hand, the remaining 90% of the monomer mixture, 0.27 parts of the polymerization chain transfer agent, 60 parts of MEK and 2.2 parts of azo radical polymerization initiator (V-65) were put into the dropping funnel. In the same manner as in Preparation Example 1, a water-insoluble polymer solution (e) having a carboxy group (weight average molecular weight of the polymer: 11000, acid value of 150 mgKOH / g) was obtained.

Preparation Examples 6-9
In Preparation Example 5, water-insoluble polymer solutions (f) to (f) having a carboxy group in the same procedure as Preparation Example 5 except that the mixing amount of acrylic acid, styrene, and α-methylstyrene was changed as shown in Table 1. i) was obtained. The results are shown in Table 1.

<Production of water-insoluble dye aqueous dispersion A>
Production Example 1
25 parts of a polymer obtained by drying the water-insoluble polymer solution (a) having a carboxy group obtained in Preparation Example 1 under reduced pressure was mixed with 78.6 parts of MEK, and further 5N sodium hydroxide aqueous solution (sodium hydroxide solid content) 16.9%, manufactured by Wako Pure Chemical Industries, Ltd., for volumetric titration) and neutralized so that the ratio of the number of moles of sodium hydroxide to the number of moles of carboxy groups in the polymer is 50%. (Neutralization degree 50%) and 400 parts of ion-exchanged water were further added. The Tyndall phenomenon was observed for the polymer in the aqueous medium, and it was confirmed that the polymer was insoluble in water.
Next, 100 parts of sublimable yellow disperse dye (CI Disperse Yellow 54, manufactured by Arimoto Chemical Industry Co., Ltd., trade name: Plast Yellow 8040) was added, and Disper (Asada Tekko Co., Ltd., Ultra Disper: trade name) ) At 20 ° C. for 60 minutes under the condition of rotating the disper blade at 7000 rpm.
The obtained mixture was subjected to 10-pass dispersion treatment with a microfluidizer (trade name, manufactured by Microfluidics) at a pressure of 200 MPa. After adding 250 parts of ion-exchanged water to the obtained dispersion and stirring, MEK was completely removed at 60 ° C. under reduced pressure, a part of water was further removed, and a 5 μm filter (acetylcellulose membrane, outer diameter). : 2.5 cm, manufactured by Fuji Film Co., Ltd.) and filtered with a 25 mL needleless syringe (Terumo Co., Ltd.) to remove coarse particles, thereby dispersing a water-insoluble dye in water with a solid concentration of 20%. Body A1 was obtained. The results are shown in Table 2.

Production Examples 2-9
In Production Example 1, instead of the water-insoluble polymer solution (a) having a carboxy group obtained in Preparation Example 1, the water-insoluble polymer solution (b) obtained in Preparation Example 2 and the water obtained in Preparation Example 3 were used. Insoluble polymer solution (c), water-insoluble polymer solution (d) obtained in Preparation Example 4, water-insoluble polymer solution (e) obtained in Preparation Example 5, water-insoluble polymer solution (f) obtained in Preparation Example 6 (f) ), The water-insoluble polymer solution (g) obtained in Preparation Example 7, the water-insoluble polymer solution (h) obtained in Preparation Example 8, or the water-insoluble polymer solution (i) obtained in Preparation Example 9 under reduced pressure. The water-insoluble dye aqueous dispersions A2 to A9 were prepared in the same procedure as in Production Example 1, except that 25 parts of the resulting polymer was added and the amount of 5N sodium hydroxide aqueous solution added was changed to 50% neutralization. Got. The results are shown in Table 2.

Production Example 10
In Production Example 8 shown in Table 1, the water-insoluble dye aqueous dispersion A10 was prepared in the same procedure as in Production Example 8, except that the amount of 5N sodium hydroxide aqueous solution was changed and the degree of neutralization was changed to 30 mol%. Obtained. The results are shown in Table 2.

Production Example 11
In Production Example 7 shown in Table 1, the water-insoluble dye aqueous dispersion A11 was prepared in the same procedure as in Production Example 7, except that the amount of 5N sodium hydroxide aqueous solution was changed and the degree of neutralization was changed to 40 mol%. Obtained. The results are shown in Table 2.

Production Examples 12 and 13
In Production Example 7 shown in Table 1, 5.4 parts of triethylamine (Production Example 12; neutralization degree 50 mol%) or 13.0 parts of 5N aqueous potassium hydroxide solution (Production Example 13) was used instead of 5N sodium hydroxide aqueous solution. Water-insoluble dye aqueous dispersions A12 to A13 were obtained in the same manner as in Production Example 7, except that the neutralization degree was 50 mol%. The results are shown in Table 2.

Production Example 14
In Production Example 7 shown in Table 1, instead of the sublimable yellow disperse dye (CI disperse yellow 54), the sublimable red disperse dye (CI disperse thread 60, manufactured by Arimoto Chemical Co., Ltd.) (Product name: Plast Red 8375-N) A water-insoluble dye aqueous dispersion A14 was obtained in the same manner as in Production Example 7, except that 100 parts was used. The results are shown in Table 2.

<Production of water-insoluble dye aqueous dispersion B>
Example 1
100 parts (solid content 20%) of the water-insoluble dye aqueous dispersion A2 obtained in Production Example 2 is placed in a glass bottle with a screw cap, and three water-insoluble polyfunctional epoxy compounds (crosslinking agents) are contained in one molecule. Trimethylolpropane polyglycidyl ether having an epoxy group (manufactured by Nagase ChemteX Corp., Denacol EX-321, molecular weight 302, epoxy value 140, water solubility 27%) 1.20 parts (crosslinking degree 50 mol%) was added and sealed. The mixture was heated at 70 ° C. for 5 hours while stirring with a stirrer. After 5 hours, ion-exchanged water was added to adjust the water-insoluble dye concentration to 15%, the temperature was lowered to room temperature, and a 5 μm filter (acetylcellulose membrane, outer diameter: 2.5 cm, manufactured by Fuji Film Co., Ltd.) was used. It filtered with the needle-less syringe (made by Terumo Corporation) of the capacity | capacitance 25mL attached, and water-insoluble dye water dispersion B1 (water-insoluble dye density | concentration: 15%, the weight average molecular weight of the polymer dispersing agent after bridge | crosslinking: 150,000, An average particle size of the dye-containing crosslinked polymer particles: 104 nm) was obtained.

Examples 2 to 13 and Comparative Examples 1 to 6
Using the water-insoluble dye water dispersion A shown in Table 3, water-insoluble dye water dispersions B2 to B13 and B15 to B20 were obtained in the same procedure as in Example 1 except that the conditions shown in Table 3 were used. .

Example 14
In Example 4 shown in Table 3, instead of trimethylolpropane polyglycidyl ether, water-soluble polyglycerol polyglycidyl ether (manufactured by Nagase ChemteX Corporation, Denacol EX-521, epoxy value 183, water content 100%) 1 A water-insoluble dye aqueous dispersion B14 was obtained in the same manner as in Example 4 except that .57 parts was used.

<Preparation of water-based ink and evaluation test>
(Preparation of water-based ink)
Using each water-insoluble dye aqueous dispersion B obtained in Examples and Comparative Examples, the concentration of water-insoluble dye with respect to the whole water-based ink is 5%, glycerin (made by Kao Corporation, concentrated glycerin for cosmetics), 5%, propylene glycol ( Wako Pure Chemical Industries, Ltd., reagent) 10%, nonionic surfactant (manufactured by Kawaken Fine Chemical Co., Ltd., trade name: acetylenol E100, 2,4,7,9-tetramethyl-5-decyne-4, 7-diol ethylene oxide 10 mol adduct) 0.5%, add ion-exchanged water, weigh so that the total amount becomes 100%, stir with a magnetic stirrer and mix well, and add a 1.2 μm filter ( A water-based ink was obtained by filtering with a 25 mL needleless syringe equipped with an acetylcellulose membrane, outer diameter: 2.5 cm, manufactured by Fujifilm Corporation.
The following tests 1 to 4 were performed using the obtained water-based ink. The results are shown in Table 3.

Test 1 (storage stability evaluation)
Each water-insoluble dye ink was sealed in a screw tube manufactured by Marum Co., Ltd. and allowed to stand in a temperature-controlled room set at 23 ° C., 40 ° C. and 70 ° C. for 1 week, and the average particle size was measured. The average particle size increase rate was calculated from the equation. The smaller the average particle size increase rate, the more the aggregation is suppressed and the storage stability is excellent.
Average particle diameter increase rate (%) = [(average particle diameter of ink after storage at 23 ° C., 40 ° C. or 70 ° C.−average particle diameter of ink before storage) / average particle diameter of ink before storage] × 100
The average particle size increase rate is a test conducted at 23 ° C. in order to confirm the fluctuation width of the measurement, but when this exceeds 5%, the change is not a fluctuation, which means that the storage stability is remarkably poor. To do. When the test at 40 ° C. is within 10% and the test at 70 ° C. is within 20%, the ink can be practically used. Moreover, it is suitable as an inkjet ink that the test at 40 ° C. is within 5% and the test at 70 ° C. is within 10%.

Test 2 (Redispersibility evaluation)
5% glycerin, 10% triethylene glycol (manufactured by Wako Pure Chemical Industries, Ltd., reagent), 0.5% acetylenol E100, add ion-exchanged water, weigh to 100% total, magnetic stirrer And stirred well to prepare a vehicle for evaluation of redispersibility.
10 μL of each water-based ink was dropped on a slide glass using a micropipette and left in an environment of 60 ° C. and 40% RH for 24 hours to evaporate and dry the water-based ink. 200 μL of a vehicle for evaluation of redispersibility was dropped on a solid material on a slide glass, and the redispersibility of the solid material was visually observed and evaluated according to the following evaluation criteria.
(Evaluation criteria)
A: The solid was uniformly redispersed.
B: The solid was redispersed, but there was a residue.
C: The solid matter was not redispersed.
If it is A or B, it is practical as an inkjet ink.

Test 3 (Evaluation of clogging of discharge nozzle)
The water-based ink prepared above is loaded into a black cartridge of an inkjet printer (Seiko Epson Corporation, model number: EM-930C, piezo method), and in a 23 ° C. and 50 RH environment, in a photo mode condition, 300 mm in length and width After performing 400 mm single color / filled printing 10 times, a nozzle check pattern was printed from the maintenance menu and evaluated (Evaluation I).
Further, while the nozzle check pattern was being printed again, when the head did not return to the home position, the power cord was disconnected from the outlet and left for one week. One week later, the power cord was plugged into the outlet, and the nozzle check pattern was printed again from the maintenance menu and evaluated (Evaluation II).
The nozzle check pattern was evaluated based on the following evaluation criteria.
(Evaluation criteria)
A: All nozzles discharged without cleaning.
B: Although there was disorder in the nozzle check pattern, all nozzles ejected when the nozzle check pattern was printed after one cleaning operation.
C: After the nozzle check pattern was printed in B, when the nozzle check pattern was printed after one more cleaning operation, all nozzles were ejected.
D: After printing the nozzle check pattern in C, when a nozzle check pattern was printed after one cleaning operation, there were nozzles that did not discharge.
Any evaluation of A, B, and C can be used as an inkjet ink.

Test 4 (Textile dyeing test)
Ink jet printer polyester fabric (manufactured by Takahashi Shoten Co., Ltd) Name: Inkjet Ponzi IJP061) was printed in monochrome and filled with a solid color of 300 mm length and 400 mm width. Next, the printed cloth was heat-pressed on a hot plate at 200 ° C. and 60 kPa for 1 minute, dyed by sublimation transfer. The obtained dyed cloth was allowed to stand for 1 day, and the image density at any 10 locations was measured using an optical densitometer SpectroEye (manufactured by Gretag Macbeth Co.) to obtain an average value.
(Evaluation criteria)
A: 1.05 or more and less than 1.10 B: 1.00 or more and less than 1.05 C: 0.95 or more and less than 1.00 D: Less than 0.95 Although C and D can be used as inkjet inks, , A or B is desirable.

  From Table 3, even if the water-insoluble dye ink of Examples 1-14 was compared with the water-insoluble dye ink of Comparative Examples 1-6, even if the volatile component volatilized at the ink discharge nozzle and the solid content concentration increased, Excellent redispersibility prevents clogging of the discharge nozzles, and has high storage stability that can maintain the performance immediately after production even when ink containing ink solvents such as organic solvents is stored at high temperatures. Furthermore, it can be seen that a high image density can be obtained.

Claims (13)

  A water-insoluble dye aqueous dispersion containing a water-insoluble dye, a water-insoluble polymer dispersant having an acid value of 80 mgKOH / g or more and 170 mgKOH / g or less and a weight average molecular weight of 100,000 or more, and water. The polymer dispersant has a crosslinked structure obtained by reacting a polymer (A) having a carboxy group having an acid value of 200 mgKOH / g or more and 320 mgKOH / g or less with a water-insoluble polyfunctional epoxy compound, and a polymer ( The water insoluble according to claim 1, wherein at least a part of the carboxy group of A) is neutralized with an alkali metal compound, and the acid value, the degree of neutralization, and the degree of crosslinking of the polymer (A) satisfy the following condition 1. Dye water dispersion.
Condition 1: The value of [(100−degree of neutralization−degree of crosslinking) / 100] × (acid value of polymer (A)) is from −30 mgKOH / g to 130 mgKOH / g.
Here, the degree of neutralization is the percentage (mol%) of “number of molar equivalents of alkali metal compound / number of molar equivalents of carboxy group of polymer (A)”, and the degree of crosslinking is “mol of epoxy group of water-insoluble polyfunctional epoxy compound”. It is a percentage ratio (mol%) of “the number of equivalents / the number of molar equivalents of carboxy groups of the polymer (A)”.   The water-insoluble dye aqueous dispersion according to claim 1 or 2, wherein a mass ratio of the water-insoluble dye to the polymer dispersant [water-insoluble dye / polymer dispersant] is 0.5 or more and 8 or less.   The water-insoluble dye is C.I. I. Disperse Yellow 54, C.I. I. Disperse Yellow 82, C.I. I. Disperse Orange 25, C.I. I. Disperse thread 60, C.I. I. Disperse Blue 72, C.I. I. Disperse blue 359, and C.I. I. The water-insoluble dye aqueous dispersion according to claim 1, which is one or more sublimable dyes selected from Disperse Violet 28.   The water-insoluble dye aqueous dispersion according to any one of claims 2 to 4, wherein the water-insoluble polyfunctional epoxy compound is a glycidyl ether compound of a polyhydric alcohol having a hydrocarbon group having 3 to 8 carbon atoms.   The water-insoluble dye aqueous dispersion according to any one of claims 2 to 5, wherein the degree of neutralization of the polymer (A) is 20 mol% or more and 80 mol% or less.   The polymer (A) is a structural unit derived from one or more carboxy group-containing vinyl monomers selected from acrylic acid and methacrylic acid, and an alkyl group having 1 to 22 carbon atoms or an aryl group having 6 to 22 carbon atoms. The water-insoluble dye water according to any one of claims 2 to 6, which is a vinyl polymer containing a structural unit derived from at least one hydrophobic monomer selected from an acrylate monomer, a methacrylate monomer and an aromatic group-containing monomer. Dispersion.   The water-insoluble dye aqueous dispersion according to any one of claims 1 to 7, which is used for transfer dyeing.   A water-based ink for inkjet recording, comprising the water-insoluble dye aqueous dispersion according to any one of claims 1 to 8 and an organic solvent.   An ink jet recording method for recording on a sheet-like recording medium using the water-based ink according to claim 9.   A transfer dyeing method, wherein the intermediate transfer medium recorded by the ink jet recording method according to claim 10 and the object to be dyed are overlapped and heated, and the dye applied to the intermediate transfer medium is sublimated and transferred to the object to be dyed. .   The transfer dyeing method according to claim 11, wherein the object to be dyed is a fabric.   The transfer dyeing method according to claim 12, wherein the fabric is a polyester fabric.