JP7000996B2 - Aqueous inkjet composition - Google Patents

Description

The present invention relates to an aqueous inkjet composition.

In recent years, the use of inkjet printing has expanded, and it has been applied not only to printing machines for offices and homes, but also to commercial printing and textile printing.
Inkjet inks containing fluorescent dyes are also used.

Examples of fluorescent dyes having excellent fluorescence intensity include C.I. I. Solvent Yellow 160: 1, C.I. I. Disperse Yellow 82 and C.I. I. There is Disperse Yellow 184.

However, when trying to apply these fluorescent dyes to inkjet inks, there is a problem that the storage stability of the inkjet inks is lower than that of other coloring materials, and foreign substances are likely to be generated in the inkjet inks during storage. there were.

For the purpose of improving the dispersibility of the fluorescent dye, an anionic dispersant and an ethylene oxide adduct of phytosterol, an ethylene oxide adduct of hydrogenated phytosterol, an ethylene oxide adduct of cholestanol, and an ethylene oxide adduct of hydrogenated cholestanol. An ink containing a compound comprising the above has been proposed (see Patent Document 1).

However, in the inkjet ink containing the above fluorescent dye, the problems of grain increase, thickening, and generation of foreign matter cannot be sufficiently suppressed when the ink is stored for a long period of time or placed in an environment where heat stress is applied. Inkjet ink ejection failure was likely to occur due to nozzle clogging.

In order to solve such a problem, it is conceivable to use a dispersant having a relatively high hydrophobicity as a dispersant for improving the dispersibility of the fluorescent dye as described above. Contrary to this, since the water solubility is low, when the inkjet ink is placed in a state where it is easy to dry, for example, when the nozzle is idle or left for a long period of time, the solid content of the inkjet ink is particularly liable to precipitate. When the solid content is deposited, the head filter and the nozzle are clogged, which leads to poor ejection of the inkjet ink.

In order to suppress the precipitation of solid content of the inkjet ink due to such drying and the occurrence of defects due to it, it is effective to use a dispersant having low hydrophobicity, for example, a dispersant having a sulfo group. In this case, the tendency that the storage stability of the inkjet ink as described above is lowered becomes more remarkable.

International Publication WO2005 / 121263 Gazette

That is, in the inkjet ink containing the fluorescent dye as described above, it is difficult to achieve both storage stability and resistance to clogging of the head filter and the nozzle due to drying.

The present invention has been made to solve the above-mentioned problems, and can be realized as the following application examples.

The composition for an aqueous inkjet according to an application example of the present invention is described in C.I. I. Solvent Yellow 160: 1, C.I. I. Disperse Yellow 82 and C.I. I. At least two dye components selected from the specific yellow dye group consisting of Disperse Yellow 184, and
It is characterized by containing a sulfonic acid-based dispersant, which is a dispersant having a chemical structure of at least one of a sulfo group and a salt of the sulfo group.

Further, in the aqueous inkjet composition according to another application example of the present invention, when one component having the highest content among the dye components constituting the specific yellow dye group is used as the first dye component, the specific one is specified. The content of the first dye component with respect to the entire yellow dye group is 50.0% by mass or more and 99.9% by mass or less.

Further, in the aqueous inkjet composition according to another application example of the present invention, one component having the highest content among the dye components constituting the specific yellow dye group is used as the first dye component, and the specific yellow dye is used. Of the dye components constituting the group, one component having the same content as the first dye component or having the highest content next to the first dye component is used as the second dye component, and is used as an aqueous inkjet composition. When the content of the first dye component in the composition is X1 [mass%] and the content of the second dye component in the aqueous inkjet composition is X2 [mass%], 0.001 ≦ X2. The relationship of / X1 ≦ 1.0 is satisfied.

Further, in the aqueous inkjet composition according to another application example of the present invention, one component having the highest content among the dye components constituting the specific yellow dye group is C.I. I. Solvent Yellow 160: 1.

Further, in the aqueous inkjet composition according to another application example of the present invention, the sulfonic acid-based dispersant is a combination of a formalin condensate of sodium naphthalene sulfonate, sodium lignin sulfonate, and sodium styrene-styrene sulfonate. At least one selected from the group consisting of polymers.

Further, in the aqueous inkjet composition according to another application example of the present invention, the content of the specific yellow dye group was set to XD [mass%], and the content of the sulfonic acid-based dispersant was set to XS [mass%]. When, the relationship of 0.2 ≦ XS / XD ≦ 5.0 is satisfied.

Further, in the aqueous inkjet composition according to another application example of the present invention, the content of the specific yellow dye group is 0.6% by mass or more and 26% by mass or less.

Further, in the aqueous inkjet composition according to another application example of the present invention, the component having the highest content among the dye components constituting the specific yellow dye group is C.I. I. Solvent Yellow 160: 1,
C.I. for the entire specific yellow dye group. I. The content of Solvent Yellow 160: 1 is 60.0% by mass or more and 99.0% by mass or less.
C.I. in the aqueous inkjet composition. I. The content of Solvent Yellow 160: 1 is 0.5% by mass or more and 25.0% by mass or less.

Further, in the aqueous inkjet composition according to another application example of the present invention, the content of the sulfonic acid-based dispersant is 0.5% by mass or more and 20% by mass or less.

Hereinafter, preferred embodiments of the present invention will be described in detail.
<Composition for water-based inkjet>
Among various fluorescent dyes, C.I. I. Solvent Yellow 160: 1, C.I. I. Disperse Yellow 82 and C.I. I. While the Disperse Yellow 184 has features such as excellent fluorescence intensity, it has the following problems. That is, the above-mentioned fluorescent dye has both the storage stability of the aqueous inkjet composition and the resistance to clogging of the head filter and the nozzle due to drying when conventionally used as a constituent component of the aqueous inkjet composition. It was difficult to do.

Therefore, the present inventor makes the best use of the excellent characteristics of the above-mentioned fluorescent dye, the storage stability of the aqueous inkjet composition containing the fluorescent dye, and the difficulty of clogging of the head filter and the nozzle due to drying. As a result of diligent research for the purpose of achieving both, the present invention has been reached.

That is, the composition for an aqueous inkjet of the present invention is C.I. I. Solvent Yellow 160: 1, C.I. I. Disperse Yellow 82 and C.I. I. It contains at least two dye components selected from the specific yellow dye group consisting of Disperse Yellow 184, and a sulfonic acid-based dispersant which is a dispersant having a chemical structure of at least one of a sulfo group and a salt of a sulfo group. It is characterized by that.

With such a configuration, an aqueous inkjet composition that exhibits both the excellent characteristics of the dye component (specific yellow dye), storage stability, and resistance to clogging of the head filter and nozzle due to drying. Can be provided.

Such an excellent effect can be obtained by using a sulfonic acid-based dispersant having a chemical structure of at least one of a highly hydrophilic sulfo group and a salt of the sulfo group, so that the composition for water-based inkjet in a nozzle or the like can be obtained. At least two specific yellow dyes (CI Solvent Yellow 160: 1) that can effectively prevent the drying of substances and have a common chemical structure, a coumarin skeleton, but a different chemical structure as a whole compound. , At least two dye components selected from the specific yellow dye group consisting of CI Disperse Yellow 82 and CI Disperse Yellow 184) in the case of containing only one specific yellow dye. In comparison, it is considered that this is because it is possible to effectively prevent the crystallization of the specific yellow dye, particularly the precipitation of crystals having a predetermined size or larger.

It is considered that the reason why the crystallization of the specific yellow dye can be prevented is as follows. That is, as described above, since the specific yellow dyes constituting the specific yellow dye group have a coumarin skeleton as a common chemical structure, they can be stabilized in a state where a plurality of molecules are close to each other during storage or the like. However, since each specific yellow dye has a different chemical structure as a whole compound, an excessive number of specific yellow dye molecules are prevented from aggregating. Therefore, even if the specific yellow dye molecule is aggregated, the aggregate is difficult to grow into a coarse crystal, and when used in combination with a sulfonic acid-based dispersant, the dispersed state can be stably maintained as an extremely small aggregate. This is thought to be due to the re-decomposition and re-diffusion of the aggregates.

On the other hand, if the above conditions are not satisfied, satisfactory results cannot be obtained.
For example, when only one specific yellow dye is used and two or more specific yellow dyes are not used in combination, the storage stability of the aqueous inkjet composition is low, and foreign substances are contained in the aqueous inkjet composition during storage. Is likely to occur.

Further, when another fluorescent dye is used instead of the specific yellow dye and the specific yellow dye is not used, it is difficult to obtain sufficient fluorescence intensity in the recording unit formed by using the aqueous inkjet composition. Is. In the present specification, the "recording unit" is applied to a thermal transfer printing method such as sublimation printing by applying the aqueous inkjet composition to the portion of the recording medium to which the aqueous inkjet composition is applied by the inkjet method. It is a concept including a site to which the constituents of the aqueous inkjet composition are transferred.

Further, when the sulfonic acid-based dispersant is not used, it becomes difficult to sufficiently improve the dispersion stability in the aqueous inkjet composition, and foreign substances are generated in the aqueous inkjet composition during storage. It's easy to do.

Further, when a dispersant other than the sulfonic acid-based dispersant is used, for example, a dispersant having a functional group having a higher hydrophobicity than the sulfo group such as a carboxyl group, instead of the sulfonic acid-based dispersant. When the inkjet ink as the aqueous inkjet composition is placed in a state where it is easy to dry, for example, when the nozzle is idle or left for a long period of time, the solid content of the aqueous inkjet composition is particularly likely to precipitate. , Poor ejection of the aqueous inkjet composition due to clogging of the head filter or nozzle is likely to occur.

In the present specification, the aqueous inkjet composition is a concept including not only the ink itself ejected by the inkjet method but also the undiluted solution used for preparing the ink. In other words, the aqueous inkjet composition of the present invention may be discharged as it is by an inkjet method, or may be discharged by an inkjet method after a treatment such as dilution. good.

[Specific yellow dye]
Aqueous inkjet compositions are described in C.I. I. Solvent Yellow 160: 1, C.I. I. Disperse Yellow 82 and C.I. I. It contains at least two specific yellow dyes selected from the specific yellow dye group consisting of Disperse Yellow 184.

All of these specific yellow dyes are yellow fluorescent dyes and have a chemical structure having a coumarin skeleton, but the chemical structures of the compounds as a whole are different from each other.

By containing two or more such specific yellow dyes together with the sulfonic acid-based dispersant described in detail later, most of them are present in a stable dispersed state in the composition for aqueous inkjet.

When one component having the highest content among the dye components constituting the specific yellow dye group is used as the first dye component, the content of the first dye component with respect to the entire specific yellow dye group is 50.0% by mass or more. It is preferably 99.9% by mass or less, more preferably 60.0% by mass or more and 99.5% by mass or less, and further preferably 70.0% by mass or more and 98.0% by mass or less.

As a result, the fluorescence intensity and color tone of the recorded material formed by using the aqueous inkjet composition can be made more suitable, and the storage stability of the aqueous inkjet composition can be further improved.

If two or more of the specific yellow dyes constituting the specific yellow dye group are contained at the same content and there is no specific yellow pigment contained at a higher content than these specific yellow dyes, One of the above-mentioned specific yellow dyes having the same content is used as the first dye component. For example, C.I. I. Solvent Yellow 160: 1 content was 35.0% by mass, C.I. I. The content of Disperse Yellow 82 was 35.0% by mass, and C.I. I. When the content of Disperse Yellow 184 is 30.0% by mass, C.I. I. Solvent Yellow 160: 1 and C.I. I. One of Disperse Yellow 82 is used as the first dye component. Further, for example, C.I. I. Solvent Yellow 160: 1 content, C.I. I. The content of Disperse Yellow 82, and C.I. I. When the content of Disperse Yellow 184 is 33.3% by mass (100/3% by mass) and is the same, C.I. I. Solvent Yellow 160: 1, C.I. I. Disperse Yellow 82 and C.I. I. Any one of Disperse Yellow 184 is used as the first dye component.

One component having the highest content among the dye components constituting the specific yellow dye group is set as the first dye component, and the content is the same as that of the first dye component among the dye components constituting the specific yellow dye group. One component having the highest content next to the first dye component is used as the second dye component, and the content of the first dye component in the water-based inkjet composition is X1 [mass%] in the water-based inkjet composition. When the content of the second dye component in the above is X2 [mass%], it is preferable to satisfy the relationship of 0.001 ≦ X2 / X1 ≦ 1.0, and 0.01 ≦ X2 / X1 ≦ 0.8. It is more preferable to satisfy the relationship of 0.02 ≦ X2 / X1 ≦ 0.5, and it is further preferable to satisfy the relationship of 0.02 ≦ X2 ≦ 0.5.

As a result, the fluorescence intensity and color tone of the recorded material formed by using the aqueous inkjet composition can be made more suitable, and the storage stability of the aqueous inkjet composition can be further improved.

If two or more of the specific yellow dyes constituting the specific yellow dye group are contained at the same content and there is no specific yellow pigment contained at a higher content than these specific yellow dyes, One of the above-mentioned specified yellow dyes having the same content is used as the first dye component, and the other one of the above-mentioned specified yellow dyes having the same content is the other one (dye component other than the first dye component). ) Is the second dye component. For example, C.I. I. Solvent Yellow 160: 1 content was 35.0% by mass, C.I. I. The content of Disperse Yellow 82 was 35.0% by mass, and C.I. I. When the content of Disperse Yellow 184 is 30.0% by mass, C.I. I. Solvent Yellow 160: 1 and C.I. I. One of Disperse Yellow 82 was used as the first dye component, and C.I. I. Solvent Yellow 160: 1 and C.I. I. The other of the Disperse Yellow 82 (a dye component that is not the first dye component) is used as the second dye component. Further, for example, C.I. I. Solvent Yellow 160: 1 content, C.I. I. The content of Disperse Yellow 82, and C.I. I. When the content of Disperse Yellow 184 is 33.3% by mass (100/3% by mass) and is the same, C.I. I. Solvent Yellow 160: 1, C.I. I. Disperse Yellow 82 and C.I. I. One of Disperse Yellow 184 is used as the first dye component, and C.I. I. Solvent Yellow 160: 1, C.I. I. Disperse Yellow 82 and C.I. I. The other one of Disperse Yellow 184 (one of the two dye components that is not the first dye component) is used as the second dye component.

In the aqueous inkjet composition, at least C.I. I. It is preferable to contain Solvent Yellow 160: 1, and one component (first dye component) having the highest content among the dye components constituting the specific yellow dye group is C.I. I. It is preferably Solvent Yellow 160: 1.

As a result, the fluorescence intensity and color tone of the recorded material formed by using the aqueous inkjet composition can be made more suitable, and the storage stability of the aqueous inkjet composition can be further improved.

In particular, C.I. I. The ratio of Solvent Yellow 160: 1 is preferably 60.0% by mass or more and 99.0% by mass or less, more preferably 62.0% by mass or more and 98.5% by mass or less, and 64.0% by mass. It is more preferably% or more and 98.0% by mass or less.

As a result, the fluorescence intensity and color tone of the recorded material formed by using the aqueous inkjet composition can be made more suitable, and the storage stability of the aqueous inkjet composition can be further improved.

The composition for water-based inkjet is C.I. I. When Solvent Yellow 160: 1 is included, it is particularly preferable to satisfy the following conditions. That is, the component having the highest content rate (first dye component) among the dye components constituting the specific yellow dye group is C.I. I. Solvent Yellow 160: 1, C.I. for the entire specific yellow dye group. I. The content of Solvent Yellow 160: 1 is 60.0% by mass or more and 99.0% by mass or less, and C.I. I. It is preferable that the content of Solvent Yellow 160: 1 is 0.5% by mass or more and 25.0% by mass or less.

As a result, the fluorescence intensity and color tone of the recorded material formed by using the aqueous inkjet composition can be made more suitable, and the storage stability of the aqueous inkjet composition can be further improved.

The average particle size of the specific yellow dye in the aqueous inkjet composition is preferably 50 nm or more and 250 nm or less, more preferably 75 nm or more and 200 nm or less, and further preferably 100 nm or more and 150 nm or less.

This further improves the storage stability of the aqueous inkjet composition. In addition, the recording unit formed by using the aqueous inkjet composition can be sublimated more effectively, and can be more preferably applied by sublimation printing.

In the present specification, the average particle size refers to a volume-based average particle size unless otherwise specified. The average particle size can be determined, for example, by measurement using Microtrac UPA (manufactured by Nikkiso Co., Ltd.).

The content of the specific yellow dye group in the composition for aqueous inkjet is preferably 0.6% by mass or more and 26% by mass or less, and more preferably 1.0% by mass or more and 23% by mass or less. It is more preferably 0.0% by mass or more and 17% by mass or less.

As a result, higher color density and fluorescence intensity can be obtained in the recording unit formed by using the aqueous inkjet composition, and the storage stability of the aqueous inkjet composition can be further improved.

In particular, when the water-based inkjet composition is the ink itself ejected by the inkjet method, the content of the specific yellow dye group in the ink is preferably 0.6% by mass or more and 17% by mass or less. It is more preferably 0.0% by mass or more and 14% by mass or less, and further preferably 2.0% by mass or more and 9.0% by mass or less.

When the aqueous inkjet composition is a stock solution used for preparing an ink ejected by an inkjet method, the content of the specific yellow dye group in the stock solution is 8.0% by mass or more and 26% by mass or less. It is preferable that it is 9.0% by mass or more and 23% by mass or less, and further preferably 10% by mass or more and 17% by mass or less.

[Sulfonic acid-based dispersant]
The composition for aqueous inkjet of the present invention contains a sulfonic acid-based dispersant, which is a dispersant having a chemical structure of at least one of a sulfo group and a salt of the sulfo group.

The sulfonic acid-based dispersant mainly has a function of improving the dispersibility of the above-mentioned specific yellow dye while effectively preventing the precipitation of solid content of the inkjet ink due to drying when applied to a recording device by the inkjet method. have.

The sulfonic acid-based dispersant is not particularly limited as long as it has a chemical structure of at least one of a sulfo group and a salt of the sulfo group, that is, a structure that ionizes to -SO _3- ^, but is not limited to naphthalene. Preferably at least one selected from the group consisting of formalin condensates of sodium sulfonate, sodium lignin sulfonate, and copolymers of styrene-sodium styrene sulfonate, formalin condensates of sodium naphthalene sulfonate, And, it is more preferable that it is at least one selected from the group consisting of a copolymer of styrene-styrene sulfonate sodium. In particular, the sum of the ratio of the formalin condensate of sodium naphthalene sulfonate and the ratio of the copolymer of styrene-sodium styrene sulfonate to the total sulfonic acid-based dispersant constituting the aqueous inkjet composition is 50% by mass. It is preferably 100% by mass or less, and more preferably 70% by mass or more and 100% by mass or less.

As a result, it is possible to prevent the precipitation of the solid content of the inkjet ink due to drying and to improve the dispersibility of the specific yellow dye at a higher level.

When the content of the specific yellow dye group in the aqueous inkjet composition is XD [mass%] and the content of the sulfonic acid-based dispersant in the aqueous inkjet composition is XS [mass%], 0.2 ≦ It is preferable to satisfy the relationship of XS / XD≤5.0, more preferably the relationship of 0.3≤XS / XD≤2.5, and the relationship of 0.4≤XS / XD≤2.0. It is more preferable to satisfy.

As a result, the fluorescence intensity and color tone of the recorded material formed by using the aqueous inkjet composition can be made more suitable, the storage stability of the aqueous inkjet composition, and the head filter and nozzle by drying. It is possible to achieve both the difficulty of clogging and the difficulty of clogging at a higher level.

The content of the sulfonic acid-based dispersant in the composition for aqueous inkjet is preferably 0.5% by mass or more and 20% by mass or less, and more preferably 1.0% by mass or more and 18% by mass or less. It is more preferably 2.0% by mass or more and 15% by mass or less.

This effectively prevents the content of the specific yellow dye group from becoming too low, and while exerting these functions more reliably, the effect of containing the sulfonic acid-based dispersant as described above is even more remarkable. Can be demonstrated.

In particular, when the aqueous inkjet composition is the ink itself ejected by the inkjet method, the content of the sulfonic acid-based dispersant in the ink is preferably 0.5% by mass or more and 13% by mass or less. It is more preferably 1.0% by mass or more and 12% by mass or less, and further preferably 2.0% by mass or more and 9.0% by mass or less.

When the aqueous inkjet composition is a stock solution used for preparing ink ejected by an inkjet method, the content of the sulfonic acid-based dispersant in the stock solution is 8.0% by mass or more and 20% by mass or less. It is preferably 9.0% by mass or more and 19% by mass or less, and further preferably 10% by mass or more and 18% by mass or less.

When the sulfonic acid-based dispersant constituting the aqueous inkjet composition contains a plurality of types of compounds, the total content of the plurality of types of compounds shall be adopted as the content rate.

[water]
The composition for an aqueous inkjet contains water. As this water, for example, pure water such as RO water, distilled water, or ion-exchanged water may be used.

The content of water in the aqueous inkjet composition is not particularly limited, but is preferably 30% by mass or more and 85% by mass or less, more preferably 35% by mass or more and 80% by mass or less, and 40% by mass. It is more preferably 75% by mass or less.

Thereby, the viscosity of the aqueous inkjet composition can be more reliably adjusted to a suitable value, and the ejection stability by the inkjet method can be further improved.

[Solvents other than water]
The composition for water-based inkjet may contain a solvent other than water.

Thereby, the viscosity of the aqueous inkjet composition can be suitably adjusted, and the moisturizing property of the aqueous inkjet composition can be enhanced. As a result, the droplet ejection by the inkjet method can be performed more stably.

Examples of the solvent other than water contained in the aqueous inkjet composition include glycerin, propylene glycol, 2-pyrrolidone and the like.

By containing these solvents, the evaporation rate can be slowed down due to the excellent moisturizing ability, and more stable droplet ejection can be performed.

The content of the solvent other than water contained in the aqueous inkjet composition is preferably 0% by mass or more and 45% by mass or less, more preferably 10% by mass or more and 43% by mass or less, and 15% by mass. It is more preferably 40% by mass or less.
As a result, the effect of containing a solvent other than the above-mentioned water is more remarkable.

[Surfactant]
The composition for aqueous inkjet may contain a surfactant.

As a result, the wettability of the aqueous inkjet composition with respect to the recording medium (base material) can be made more suitable, which is advantageous in obtaining better image quality.

As the surfactant contained in the aqueous inkjet composition, for example, various surfactants such as anionic surfactants, cationic surfactants, and nonionic surfactants can be used.

More specifically, examples of the surfactant contained in the aqueous inkjet composition include acetylene-based surfactants, silicone-based surfactants, and fluorine-based surfactants.

When the aqueous inkjet composition contains a silicone-based surfactant, the wettability of the aqueous inkjet composition with respect to the recording medium (base material) can be made more suitable, and an image having better gradation can be obtained. (Recording unit) can be formed.

When the aqueous inkjet composition contains a silicone-based surfactant, the content of the silicone-based surfactant in the aqueous inkjet composition is 5.0 mass by mass with respect to 100 parts by mass of the specific yellow dye group. It is preferably 100 parts by mass or more and 150 parts by mass or less, more preferably 7.0 parts by mass or more and 140 parts by mass or less, and further preferably 10 parts by mass or more and 70 parts by mass or less.

As a result, the effect of containing the above-mentioned silicone-based surfactant is more remarkable.

Examples of commercially available silicone-based surfactants include BYK-306, BYK-307, BYK-333, BYK-337, BYK-341, BYK-345, BYK-346, BYK-347, BYK-348, BYK-. 349, BYK-378 (trade name, manufactured by Big Chemie Japan), KF-351A, KF-352A, KF-353, KF-354L, KF-355A, KF-615A, KF-945, KF-640, KF 642, KF-643, KF-6020, X-22-4515, KF-6011, KF-6012, KF-6015, KF-6017 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) and the like can be mentioned.

[Sulfone group-containing coumarin skeleton compound]
The aqueous inkjet composition of the present invention may contain a sulfogroup-containing coumarin skeleton compound having a coumarin skeleton and having a chemical structure of at least one of a sulfo group and a salt of a sulfo group.

The sulfo group-containing coumarin skeleton compound is at least one of a glucone skeleton having a chemical structure in the molecule of a specific yellow dye and a sulfo group and a salt of a sulfo group having a chemical structure in the molecule of a sulfonic acid dispersant. Since it has one of the chemical structures, it has excellent affinity for specific yellow dyes and sulfonic acid-based dispersants. By including such a sulfo group-containing coumarin skeleton compound, the storage stability of the aqueous inkjet composition can be further improved. In particular, the storage stability of the aqueous inkjet composition can be further improved while fully exerting the functions of the specific yellow dye and the sulfonic acid-based dispersant as described above. In addition, the sulfo group-containing coumarin skeleton compound is a component that is unlikely to cause adverse effects in sublimation printing.

The sulfogroup-containing coumarin skeleton compound may be a component having a coumarin skeleton in the molecule and having a chemical structure of at least one of a sulfo group and a salt of the sulfo group. I. Acid Yellow 184 and C.I. I. It is preferably at least one selected from the group consisting of Acid Yellow 250.

As a result, the storage stability of the aqueous inkjet composition can be made particularly excellent while more effectively exerting the functions of the specific yellow dye and the sulfonic acid-based dispersant as described above.

In addition, C.I. I. Acid Yellow 184 has a chemical structure represented by the following formula (1), and C.I. I. Acid Yellow 250 has a chemical structure represented by the following formula (2).

When the composition for aqueous inkjet contains a sulfo group-containing coumarin skeleton compound, the content of the sulfo group-containing coumarin skeleton compound in the composition for aqueous inkjet is 0.001% by mass or more and 5.0% by mass or less. It is more preferably 0.005% by mass or more and 4.0% by mass or less, and further preferably 0.03% by mass or more and 3.0% by mass or less.

This effectively prevents the content of the specific yellow dye and the sulfonic acid-based dispersant from becoming too low, and while more reliably exerting these functions, contains the sulfo group-containing coumarin skeleton compound as described above. The effect of this can be more remarkable.

In particular, when the aqueous inkjet composition is the ink itself ejected by the inkjet method, the content of the sulfo group-containing coumarin skeleton compound in the ink is 0.001% by mass or more and 2.3% by mass or less. It is more preferable that it is 0.005% by mass or more and 1.9% by mass or less, and further preferably 0.03% by mass or more and 1.7% by mass or less.

When the aqueous inkjet composition is a stock solution used for preparing an ink ejected by an inkjet method, the content of the sulfo group-containing coumarin skeleton compound in the stock solution is 0.9% by mass or more and 5.0% by mass. % Or more, more preferably 1.4% by mass or more and 4.0% by mass or less, and further preferably 1.9% by mass or more and 3.0% by mass or less.

When the sulfo group-containing coumarin skeleton compound constituting the aqueous inkjet composition contains a plurality of types of compounds, the total content of the plurality of types of the compounds is adopted as the content rate.

When the content of the specific yellow dye group in the aqueous inkjet composition is XD [mass%] and the content of the sulfo group-containing coumarin skeleton compound is XC [mass%], 0.0005 ≦ XC / XD ≦ 2. It is preferable to satisfy the relationship of .7, more preferably to satisfy the relationship of 0.002 ≤ XC / XD ≤ 1.9, and more preferably to satisfy the relationship of 0.04 ≤ XC / XD ≤ 0.9. More preferred.

This makes it possible to achieve both the fluorescence intensity and color tone of the recorded material formed by using the aqueous inkjet composition and the storage stability of the aqueous inkjet composition at a higher level.

When the content of the sulfonic acid-based dispersant in the composition for aqueous inkjet is XS [mass%] and the content of the sulfo group-containing coumarin skeleton compound is XC [mass%], 0.0005 ≦ XC / XS ≦ It is preferable to satisfy the relationship of 2.8, more preferably the relationship of 0.005 ≦ XC / XS ≦ 1.8, and more preferably the relationship of 0.05 ≦ XC / XS ≦ 1.6. Is even more preferable.

This makes it possible to more effectively prevent the precipitation of solids in the inkjet ink due to drying, and to improve the storage stability of the aqueous inkjet composition.

[Other ingredients]
The composition for water-based inkjet may contain components (other components) other than the above-mentioned components.

Examples of other components include colorants other than the above, dispersants other than the above, triethylene glycol monomethyl ether, triethylene glycol monobutyl ether, diethylene glycol monomethyl ether, 1,2-hexanediol, 1,2-pentanediol, and the like. Penetrants such as 1,2-butanediol and 3-methyl1,5-pentanediol, pH regulators, chelating agents such as ethylenediamine tetraacetate (EDTA), preservatives / antifungal agents, rust preventives, etc. Can be mentioned. As the preservative / fungicide, for example, a compound having an isothiazolin ring structure in the molecule can be preferably used.

The content of other components (when a plurality of types of components are contained as other components, the total content of these components) is preferably 6% by mass or less, and more preferably 4% by mass or less.

In particular, when the aqueous inkjet composition of the present invention contains a dispersant (other dispersant) other than the above, the content of the dispersant (other dispersant) is preferably 5% by mass or less. It is more preferably 3% by mass or less.

The surface tension of the aqueous inkjet composition at 20 ° C. is preferably 20 mN / m or more and 50 mN / m or less, more preferably 21 mN / m or more and 40 mN / m or less, and 23 mN / m or more and 30 mN / m or less. Is more preferable.

As a result, clogging of the nozzle of the ejection device by the inkjet method is less likely to occur, and the ejection stability of the aqueous inkjet composition is further improved. Further, even if the nozzle is clogged, the recoverability by capping the nozzle (capping) can be further improved.

As the surface tension, a value measured by the Wilhelmy method can be adopted. A surface tension meter (for example, manufactured by Kyowa Interface Science Co., Ltd., CBVP-7, etc.) can be used for measuring the surface tension.

The viscosity of the aqueous inkjet composition at 20 ° C. is preferably 2 mPa · s or more and 30 mPa · s or less, more preferably 3 mPa · s or more and 20 mPa · s or less, and 4 mPa · s or more and 10 mPa · s or less. It is even more preferable to have it.
This further improves the ejection stability of the aqueous inkjet composition.

The viscosity was increased from 10 [s ^-1 ] to 1000 [s ^-1 ] using a viscoelasticity tester (for example, MCR-300 manufactured by Pysica) at 20 ° C. It can be measured by reading the viscosity at Shear Rate 200.

The aqueous inkjet composition of the present invention is usually applied to a recording device by an inkjet method in a state of being stored in a container such as a cartridge, a bag, or a tank. In other words, the recording device according to the present invention includes a container (ink cartridge or the like) for storing the aqueous inkjet composition of the present invention.

The aqueous inkjet composition of the present invention may be an ink ejected by an inkjet method or a stock solution used for preparing the ink, and the specific configuration of the device for ejecting droplets is not limited, but the aqueous composition of the present invention is limited. The composition for an inkjet includes an ink jet recording device (more specifically, for example, an ink containing container provided with an ink injection port capable of replenishing ink, and a recording head having a nozzle hole for ejecting the ink). It is preferably the one that is applied to the recording device (including the undiluted solution).

In such a recording device, when the ink containing the above-mentioned specific yellow dye is applied, there is a problem that foreign matter is particularly likely to be generated at the gas-liquid interface due to the ink coming into contact with the atmosphere. According to the invention, even when applied to such a recording device, it is possible to effectively prevent the above-mentioned problems from occurring. That is, the effect of the present invention is more remarkably exhibited when it is applied to an open-air recording device.

<Recording method>
The composition for water-based inkjet of the present invention can be applied to, for example, a direct printing method, a thermal transfer printing method (for example, sublimation printing) and the like. In particular, even when the aqueous inkjet composition contains a sulfo group-containing coumarin skeleton compound, the specific yellow dye which is a fluorescent dye has sublimation properties and is a sulfo group-containing coumarin skeleton compound which is a coloring component. Has substantially no sublimation property (in other words, the sublimation property is sufficiently lower than that of the specific yellow dye). Since the contained coumarin skeleton compound can effectively prevent the color tone of the final recorded material from being affected, it can be suitably applied to the thermal transfer printing method.

Hereinafter, an example of a thermal transfer printing method (sublimation printing) will be described as a recording method using the aqueous inkjet composition of the present invention.

The recording method according to the present embodiment is an ink adhesion step of adhering the aqueous inkjet composition to the intermediate transfer medium by an inkjet method, and heating the intermediate transfer medium to which the aqueous inkjet composition is attached to form the aqueous inkjet composition. It has a transfer step of transferring a specific yellow dye as a sublimating dye contained in a product to a recording medium.

[Ink adhesion process]
In the ink adhesion step, the aqueous inkjet composition is adhered to the intermediate transfer medium by an inkjet method. The water-based inkjet composition can be ejected by an inkjet method using a known inkjet recording device. As the ejection method, a piezo method, a method of ejecting ink by bubbles generated by heating the ink, or the like can be used. Above all, the piezo method is preferable from the viewpoint of difficulty in deteriorating the composition for water-based inkjet.

In the ink adhesion step, inks other than the aqueous inkjet composition according to the present invention may be used in combination.

[Intermediate transfer medium]
As the intermediate transfer medium, for example, paper such as plain paper, a recording medium provided with an ink receiving layer (referred to as inkjet paper, coated paper, or the like) or the like can be used. Of these, paper provided with an ink receiving layer made of inorganic fine particles such as silica is preferable. As a result, an intermediate transfer medium in which bleeding and the like are suppressed can be obtained in the process of drying the aqueous inkjet composition adhering to the intermediate transfer medium, and the specific yellow dye is further sublimated in the subsequent transfer step. It tends to proceed smoothly.

[Transfer process]
Then, the intermediate transfer medium to which the aqueous inkjet composition is attached is heated, and the specific yellow dye as a constituent component of the aqueous inkjet composition is transferred to the recording medium. As a result, a recorded material is obtained.

In particular, the specific yellow dye, which is a fluorescent dye, has sublimation properties, and the sulfogroup-containing coumarin skeleton compound, which is a coloring component, does not substantially have sublimation properties (in other words, compared to the specific yellow dyes). Since the sublimation property is sufficiently low), it is effective that the sulfogroup-containing coumarin skeleton compound is transferred to the recording medium even when the aqueous inkjet composition contains the sulfo group-containing coumarin skeleton compound. The specific yellow dye can be transferred to a recording medium while preventing the dye from being transferred to the recording medium. Therefore, the obtained recorded material exhibits the characteristics of excellent color tone and fluorescence intensity of the specific yellow dye, and even when the aqueous inkjet composition contains a sulfo group-containing coumarin skeleton compound, a sulfo group-containing coumarin skeleton. The occurrence of the influence of the color tone of the compound is effectively prevented.

The heating temperature in this step is preferably 160 ° C. or higher and 220 ° C. or lower, and more preferably 170 ° C. or higher and 200 ° C. or lower.

As a result, the energy required for transcription can be reduced, and the productivity of the recorded material can be further improved. In addition, the color development property of the obtained recorded material can be further improved.

The heating time in this step is preferably 30 seconds or more and 90 seconds or less, and more preferably 45 seconds or more and 80 seconds or less, although it depends on the heating temperature.

As a result, the energy required for transcription can be reduced, and the productivity of the recorded material can be further improved. In addition, the color development property of the obtained recorded material can be further improved.

Further, this step may be performed by heating the surface of the intermediate transfer medium to which the aqueous inkjet composition is attached in a state of facing the recording medium at regular intervals, or by heating the surface of the recording medium. Although it may be carried out by heating in a state of being in close contact with the surface, it is preferably carried out by heating the surface of the intermediate transfer medium to which the aqueous inkjet composition is attached in a state of being in close contact with the surface of the recording medium.

As a result, the energy required for transcription can be reduced, and the productivity of the recorded material can be further improved. In addition, the color development of the obtained recorded material can be further improved.

[recoding media]
The recording medium is not particularly limited, and examples thereof include cloth (hydrophobic fiber cloth and the like), resin (plastic) film, paper, glass, metal, ceramics and the like. Further, as the recording medium, a material having a three-dimensional shape such as a sheet shape, a spherical shape, or a rectangular parallelepiped shape may be used.

When the recording medium is a cloth, examples of the fibers constituting the cloth include polyester fibers, nylon fibers, triacetate fibers, diacetate fibers, polyamide fibers, and blended products using two or more of these fibers. .. Further, a blended product of these with recycled fibers such as rayon or natural fibers such as cotton, silk and wool may be used.

When the recording medium is a resin (plastic) film, examples of the resin (plastic) film include polyester film, polyurethane film, polycarbonate film, polyphenylene sulfide film, polyimide film, and polyamide-imide film.

The resin (plastic) film may be a laminated body in which a plurality of layers are laminated, or may be composed of a functionally graded material whose composition of the material changes in an inclined manner.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto.

For example, the aqueous inkjet composition of the present invention may be any one used for ejection by an inkjet method, and may not be applied to the recording method as described above.

For example, it may be applied to a method having other steps (pretreatment step, intermediate treatment step, posttreatment step) in addition to the steps as described above.

In this case, examples of the pretreatment step include a step of applying a coat layer to a recording medium.

In addition, examples of the intermediate treatment step include a step of preheating the recording medium.
Moreover, as a post-treatment step, for example, a step of cleaning a recording medium and the like can be mentioned.

Further, the aqueous inkjet composition of the present invention can be suitably applied to sublimation transfer without using an intermediate transfer medium. Sublimation transfer without using an intermediate transfer medium includes, for example, a step of adhering an aqueous ink jet composition to an ink receiving layer of a recording medium (film product or the like) provided with a peelable ink receiving layer by an inkjet method. The step of heating the recording medium provided with the ink receiving layer to which the water-based inkjet composition is attached as it is, sublimating and diffusing the ink receiving layer onto the recording medium on the lower layer side, and peeling the ink receiving layer from the recording medium. Examples thereof include a method having a step of obtaining a recorded material.

Next, specific examples of the present invention will be described.
[1] Preparation of Undiluted Solution for Inkjet Ink Production (Composition for Aqueous Inkjet) (Example A1)
First, C.I. as a specific yellow dye which is a fluorescent dye. I. Solvent Yellow 160: 1 and C.I. I. Disperse Yellow 82, a formalin condensate of sodium naphthalenesulfonate as a sulfonic acid-based dispersant, and pure water are mixed at the ratios shown in Table 1 and stirred with a Hysia mixer (manufactured by Silberson) at 3000 rpm. And made into a slurry. Then, the produced slurry and 0.5 mm diameter glass beads were stirred and dispersed under water cooling in a bead mill (LMZ015 Ashizawa Finetech Co., Ltd.) to produce an undiluted solution for producing an inkjet ink as an aqueous inkjet composition.

The average particle size of the specific yellow dye in the stock solution for producing inkjet ink was 150 nm.

(Comparative Example A1)
As a specific yellow dye, C.I. I. A stock solution for producing an inkjet ink as an aqueous inkjet composition was produced in the same manner as in Example A1 except that only Solvent Yellow 160: 1 was used and the compounding ratio of each component was as shown in Table 1.

Table 1 shows the compositions and the like of the aqueous inkjet compositions (stock solutions for producing inkjet inks) of Examples and Comparative Examples. In the table, C.I. I. Solvent Yellow 160: 1 to "SY160: 1", C.I. I. Disperse Yellow 82 was designated as "DY82", and the formalin condensate of sodium naphthalene sulfonate was designated as "C2-1". In addition, the undiluted solutions for manufacturing inkjet inks of the above-mentioned Examples and Comparative Examples have viscosities in the range of 2.0 mPa · s or more and 30 mPa · s or less, and surface tensions of 25 mN / m or more and 50 mN / m or less. It was a value within the range of. The viscosity of the Shear Rate was increased from 10 [s ^-1 ] to 1000 [s ^-1 ] at 20 ° C. using a viscoelasticity tester MCR-300 (manufactured by Pysica). It was measured by reading the viscosity of the hour. The surface tension was measured by the Wilhelmy method at 20 ° C. using a surface tension meter (CBVP-7, manufactured by Kyowa Interface Science Co., Ltd.).

[2] Evaluation of undiluted solution for manufacturing inkjet ink [2-1] Storage stability (change in particle size)
For the aqueous inkjet compositions (stock solution for inkjet ink production) of the above Examples and Comparative Examples, the average particle size of the specific yellow dye immediately after production and the case where they were placed in a predetermined container and left in an environment of 60 ° C. for 1 week, respectively. The average particle size of the specific yellow dye was obtained, and from these values, the rate of change in the average particle size of the specific yellow dye when left in an environment of 60 ° C for one week with respect to the average particle size of the specific yellow dye immediately after production. Was calculated and evaluated according to the following criteria. A Microtrac UPA (manufactured by Nikkiso Co., Ltd.) was used for measuring the average particle size. It can be said that the larger the volatility of the average particle size, the lower the storage stability.

A: The volatility of the average particle size is less than 5%.
B: The volatility of the average particle size is 5% or more and less than 10%.
C: The volatility of the average particle size is 10% or more and less than 15%.
D: The volatility of the average particle size is 15% or more and less than 20%.
E: The volatility of the average particle size is 20% or more.
These results are summarized in Table 2.

As is clear from Table 2, excellent results were obtained in the present invention. On the other hand, in the comparative example, satisfactory results were not obtained.

[3] Preparation of Inkjet Ink (Aqueous Inkjet Composition) (Example B1)
The stock solution for producing inkjet ink prepared in Example A1, glycerin, propylene glycol, BYK348 (manufactured by Big Chemie Japan) as a silicone-based surfactant, and pure water are mixed at the ratios shown in Table 3. , Inkjet ink as an aqueous inkjet composition was produced by stirring with a high shear mixer (manufactured by Silberson) at 3000 rpm.
The average particle size of the specific yellow dye in the inkjet ink was 150 nm.

(Example B2)
First, C.I. as a specific yellow dye which is a fluorescent dye. I. Solvent Yellow 160: 1 and C.I. I. Disperse Yellow 82, a copolymer of styrene-styrene sulfonate sodium as a sulfonic acid-based dispersant, glycerin, propylene glycol, BYK348 (manufactured by Big Chemie Japan) as a silicone-based surfactant, and pure water. Was mixed at the ratio shown in Table 3 and stirred with a high shear mixer (manufactured by Silberson) at 3000 rpm to form a slurry. Then, the produced slurry and 0.5 mm diameter glass beads were stirred and dispersed under water cooling in a bead mill (LMZ015 Ashizawa Finetech Co., Ltd.) to produce an inkjet ink as an aqueous inkjet composition.
The average particle size of the specific yellow dye in the inkjet ink was 150 nm.

(Examples B3 to B8)
An inkjet ink as an aqueous inkjet composition was produced in the same manner as in Example B2, except that the types of the specific yellow dye and the sulfonic acid-based dispersant and the blending ratio of each component were shown in Table 1. ..

(Comparative Example B1)
The stock solution for producing inkjet ink prepared in Comparative Example A1, glycerin, propylene glycol, BYK348 (manufactured by Big Chemie Japan) as a silicone-based surfactant, and pure water are mixed at the ratios shown in Table 3. , Inkjet ink as an aqueous inkjet composition was produced by stirring with a high shear mixer (manufactured by Silberson) at 3000 rpm. That is, the inkjet ink of this comparative example contains only one type of specific yellow dye.
The average particle size of the specific yellow dye in the inkjet ink was 150 nm.

(Comparative Example B2)
First, C.I. as a specific yellow dye which is a fluorescent dye. I. Solvent Yellow 160: 1 and C.I. I. Disperse Yellow 82, glycerin, propylene glycol, BYK348 (manufactured by Big Chemie Japan) as a silicone-based surfactant, and pure water are mixed at the ratios shown in Table 3 and mixed with a high shear mixer (Silverson). The mixture was stirred at 3000 rpm to form a slurry. Then, the produced slurry and 0.5 mm diameter glass beads were stirred and dispersed under water cooling in a bead mill (LMZ015 Ashizawa Finetech Co., Ltd.) to produce an inkjet ink as an aqueous inkjet composition. That is, the inkjet ink of this comparative example does not contain a sulfonic acid-based dispersant.
The average particle size of the specific yellow dye in the inkjet ink was 150 nm.

(Comparative Examples B3 to B6)
An inkjet ink as an aqueous inkjet composition was produced in the same manner as in Example B2, except that the types of components used for adjusting the inkjet ink and the blending ratio of each component were shown in Table 3.

Table 3 summarizes the conditions of the aqueous inkjet composition (inkjet ink) of each of the Examples and Comparative Examples. In the table, C.I. I. Solvent Yellow 160: 1 to "SY160: 1", C.I. I. Disperse Yellow 82 is referred to as "DY82", C.I. I. Disperse Yellow 184 is "DY184", sodium naphthalene sulfonate formalin condensate is "C2-1", sodium lignin sulfonate is "C2-2", and copolymer of styrene-sodium styrene sulfonate is "C2-3". , Glyserin is "Gly", propylene glycol is "PG", BYK348 as a silicone-based surfactant (manufactured by Big Chemie Japan) is "BYK348", and C.I. I. Disperse Yellow 54 is designated as "DY54", and the copolymer of styrene-sodium acrylate as another component is designated as "C2'". Further, all of the inkjet inks of Examples B1 to B8 have a viscosity in the range of 2.0 mPa · s or more and 5.0 mPa · s or less, and a surface tension of 20 mN / m or more and 35 mN / m or less. The value was within the range. The viscosity of the Shear Rate was increased from 10 [s ^-1 ] to 1000 [s ^-1 ] at 20 ° C. using a viscoelasticity tester MCR-300 (manufactured by Pysica). It was measured by reading the viscosity of the hour. The surface tension was measured by the Wilhelmy method at 20 ° C. using a surface tension meter (CBVP-7, manufactured by Kyowa Interface Science Co., Ltd.).

[4] Evaluation of inkjet ink [4-1] Storage stability (change in particle size)
For the aqueous inkjet compositions (inkjet inks) of each of the Examples and Comparative Examples, the average particle size of the dye immediately after production and the case where they were placed in a predetermined ink storage container and left in an environment of 60 ° C. for one week. The average particle size of the dye was obtained, and from these values, the rate of change in the average particle size of the dye when left in an environment of 60 ° C. for one week with respect to the average particle size of the dye immediately after production was obtained, and according to the following criteria. evaluated. A Microtrac UPA (manufactured by Nikkiso Co., Ltd.) was used for measuring the average particle size. It can be said that the larger the volatility of the average particle size, the lower the storage stability and the greater the adverse effect on the discharge stability.

A: The volatility of the average particle size is less than 5%.
B: The volatility of the average particle size is 5% or more and less than 10%.
C: The volatility of the average particle size is 10% or more and less than 15%.
D: The volatility of the average particle size is 15% or more and less than 20%.
E: The volatility of the average particle size is 20% or more.

[4-2] Clog Recovery The aqueous inkjet composition (inkjet ink) of each of the above-mentioned Examples and Comparative Examples is filled in a predetermined ink container, and the container is used as a recording device PX-H6000. Attached to (manufactured by Seiko Epson). The ink container of PX-H6000 manufactured by Seiko Epson (the above-mentioned ink container) is provided with an ink injection port capable of replenishing the water-based inkjet composition, and when attached to a recording device in a used state, it is provided. It is open to the atmosphere.

After confirming that all the nozzles were ejected normally, the power of the recording device was turned off in a normal state and left in an environment of 40 ° C. for 1 month.

After that, the number of times required to reach normal discharge by the recovery operation by suction was calculated and evaluated according to the following criteria.

A: Clean discharge immediately after the power was turned on. Alternatively, the recovery operation was normalized 1 to 3 times.
B: The recovery operation was normalized 4 to 6 times.
C: Recovery operation was normalized 7 to 9 times.
D: After 9 recovery operations, the mixture was allowed to stand at room temperature for 12 hours, and further normalized by 1 to 3 recovery operations.
E: After 9 recovery operations, the mixture was allowed to stand at room temperature for 12 hours, and even after 1 to 3 recovery operations, it did not normalize.

[4-3] Color development (fluorescence intensity)
The aqueous inkjet composition (inkjet ink) of each of the Examples and Comparative Examples was filled in a predetermined ink container, and the container was mounted on a recording device PX-H6000 (manufactured by Seiko Epson). ..

After confirming that all the nozzles were ejected normally, the inkjet ink was ejected, and a pattern with a recording resolution of 1440 × 720 dpi and an impact amount of 10% was attached to the intermediate transfer medium TRANSJET Classic (manufactured by Cham Paper). .. The operating environment of the recording device (printer) was set to 25 ° C.

After that, the adhered side of the aqueous inkjet composition of the intermediate transfer medium was brought into close contact with the cloth (100% polyester, Amina, manufactured by Toray Industries, Inc.) as a white recording medium, and in this state, a heat press machine (TP-608M, Taiyo Seiki). (Manufactured by the same company) was heated at 200 ° C. for 60 seconds, and sublimation transfer was performed to obtain each recorded material.

The fluorescence emission intensity of each of the obtained recorded materials was evaluated. Specifically, using a spectrophotometer FD-7 (manufactured by Konica Minolta Co., Ltd.), the fluorescence whitening intensity was measured three times for the pattern portion where the amount of ink applied to the cloth, which was each recorded material, was 10%, and the average value thereof was measured. Was calculated and evaluated according to the following criteria. The measurement conditions are as follows.

Color measurement method: Reflection measurement Illumination conditions: M1 [D50]
Density White standard: Absolute value Observation field of view: 2 °
Observation light source: D50
Polarizing filter: Not installed

A: The fluorescence whitening intensity is 4 or more.
B: The fluorescence whitening intensity is 3 or more and less than 4.
C: The fluorescence whitening intensity is 2 or more and less than 3.
D: The fluorescence whitening intensity is 1 or more and less than 2.
E: The fluorescence whitening intensity is less than 1.
These results are summarized in Table 4.

As is clear from Table 4, excellent results were obtained in the present invention. On the other hand, in the comparative example, satisfactory results were not obtained.

Claims (9)

C. I. Solvent Yellow 160: 1, C.I. I. Disperse Yellow 82 and C.I. I. At least two dye components selected from the specific yellow dye group consisting of Disperse Yellow 184, and
A composition for an aqueous inkjet, which comprises a sulfonic acid-based dispersant, which is a dispersant having a chemical structure of at least one of a sulfo group and a salt of the sulfo group. When one component having the highest content among the dye components constituting the specific yellow dye group is used as the first dye component, the content of the first dye component with respect to the entire specific yellow dye group is 50. The aqueous inkjet composition according to claim 1, wherein the composition is 0% by mass or more and 99.9% by mass or less. One component having the highest content among the dye components constituting the specific yellow dye group is set as the first dye component, and the same content as the first dye component among the dye components constituting the specific yellow dye group is used. The content of the first dye component in the composition for water-based inkjet is X1 [mass%], and the content of the first dye component, which is the ratio or the content next to the first dye component, is the second dye component. According to claim 1 or 2, the relationship of 0.001 ≦ X2 / X1 ≦ 1.0 is satisfied when the content of the second dye component in the aqueous inkjet composition is X2 [mass%]. Aqueous dye composition. Among the dye components constituting the specific yellow dye group, one component having the highest content is C.I. I. The composition for an aqueous inkjet according to any one of claims 1 to 3, which is Solvent Yellow 160: 1. Claim 1 to claim 1, wherein the sulfonic acid-based dispersant is at least one selected from the group consisting of a formarin condensate of sodium naphthalene sulfonate, sodium lignin sulfonate, and a copolymer of styrene-sodium styrene sulfonate. 4. The composition for an aqueous inkjet according to any one of 4. When the content of the specific yellow dye group is XD [mass%] and the content of the sulfonic acid-based dispersant is XS [mass%], the relationship of 0.2 ≦ XS / XD ≦ 5.0 is satisfied. The aqueous inkjet composition according to any one of claims 1 to 5. The aqueous inkjet composition according to any one of claims 1 to 6, wherein the content of the specific yellow dye group is 0.6% by mass or more and 26% by mass or less. Among the dye components constituting the specific yellow dye group, the component having the highest content is C.I. I. Solvent Yellow 160: 1,
C.I. for the entire specific yellow dye group. I. The content of Solvent Yellow 160: 1 is 60.0% by mass or more and 99.0% by mass or less.
C.I. in the aqueous inkjet composition. I. The aqueous inkjet composition according to any one of claims 1 to 7, wherein the Solvent Yellow 160: 1 content is 0.5% by mass or more and 25.0% by mass or less. The aqueous inkjet composition according to any one of claims 1 to 8, wherein the content of the sulfonic acid-based dispersant is 0.5% by mass or more and 20% by mass or less.