JP7167658B2 - 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 in addition to office and home printing machines, it is also applied to commercial printing, textile printing, and the like.
Inkjet inks containing disperse dyes are also used.

Such inkjet inks include a direct printing method in which ink is applied (printed) to a recording medium (usually composed of fibers) to be dyed and then the dye is dyed by heat treatment such as steaming, There is a thermal transfer printing method in which dye ink is applied (printed) to an intermediate transfer medium (dedicated transfer paper), and then the dye is sublimated and transferred from the intermediate transfer medium side to a recording medium to be dyed by heat.

Ink jet inks containing disperse dyes generally have problems of low storage stability and poor ejection stability by ink jet method due to the problem of long-term dispersion stability of disperse dyes.

In order to solve such problems, an ink composition described in Patent Document 1 has been proposed.

International Publication WO2005/121263

However, in such an ink composition, when a specific disperse dye is contained, the storage stability of the ink composition cannot be sufficiently excellent. There is a problem that clogging occurs in the head filter and nozzles during ejection by the method. In particular, as a disperse dye, C.I. I. The inventors have found that such a problem becomes conspicuous when Disperse Red 60 is used. In particular, C.I. I. An ink composition containing Disperse Red 60 tends to generate foreign matter (especially crystalline foreign matter) at the gas-liquid interface, which is particularly likely to cause clogging of head filters and nozzles during ejection by an inkjet method. I was headlining.

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

（式（１）中、Ｒ^１は、炭素数が６以下の炭化水素基、または－（ＣＨ_２）_ｍ－ＮＲ^８Ｒ^９（ただし、ｍは６以下の整数、Ｒ^８、Ｒ^９は、それぞれ独立に、水素原子または炭素数が６以下の炭化水素基）であり、ｎは１以上の整数である。）

（式（２）中、Ｒ^２、Ｒ^３のうちの一方は－ＯＨであり、他方は－ＮＲ^４Ｒ^５（だだし、Ｒ^４、Ｒ^５は、それぞれ独立に、水素原子または炭素数が６以下の炭化水素基である。）であり、ｎは１以上の整数である。）

（式（４）中、Ｒ ^７ は－ＳＯ _３ Ｈである。） [1] C.I. I. Disperse Red 60;
A group consisting of a compound represented by the following formula (1), a compound represented by the following formula (2), an ethylene oxide adduct of tristyrylphenol, and a derivative of an ethylene oxide adduct of tristyrylphenol represented by the following formula (4). a substance A that is at least one compound selected from
and an anionic dispersant.

(In formula (1), R ¹ is a hydrocarbon group having 6 or less carbon atoms, or —(CH ₂ ) _m —NR ⁸ R ⁹ (where m is an integer of 6 or less, and R ⁸ and R ⁹ are each independently a hydrogen atom or a hydrocarbon group having 6 or less carbon atoms), and n is an integer of 1 or more.)

(In formula (2), one of R ² and R ³ is —OH, and the other is —NR ⁴ R ⁵ (provided that R ⁴ and R ⁵ are each independently a hydrogen atom or a is a hydrocarbon group of 6 or less), and n is an integer of 1 or more.)

(In formula (4), R ⁷ is —SO ₃ H.)

（式（３）中、Ｒ^６は、炭素数が４以下の炭化水素基であり、ｎは１以上の整数である。） [2] The water-based inkjet according to [1] above, wherein the anionic dispersant is at least one of a compound represented by the following formula (3), a sodium salt of naphthalenesulfonic acid formalin condensate, and ligninsulfonic acid. composition.

(In formula ( ³ ), R6 is a hydrocarbon group having 4 or less carbon atoms, and n is an integer of 1 or more.)

[3] C. above. I. The above [1] or The composition for water-based inkjet according to [2].

[4] C. above. I. The above [1 ] to the water-based inkjet composition according to any one of [3].

[5] Satisfying the relationship of 0.002 ≤ XA/XB ≤ 1.5, where XA [mass%] is the content of the substance A and XB [mass%] is the content of the anionic dispersant The water-based inkjet composition according to any one of [1] to [4] above.

[6] C. above. I. The aqueous inkjet composition according to any one of [1] to [5] above, wherein the content of Disperse Red 60 is 0.1% by mass or more and 30% by mass or less.

[7] The water-based inkjet composition according to any one of [1] to [6] above, wherein the content of the substance A is 0.05% by mass or more and 8.0% by mass or less.

[8] The water-based inkjet composition according to any one of [1] to [7] above, wherein the content of the anionic dispersant is 0.1% by mass or more and 30% by mass or less.

[9] The water-based inkjet composition according to any one of [1] to [8] above, wherein the anionic dispersant has a weight average molecular weight of 1,000 to 20,000.

[10] The water-based inkjet composition according to any one of [1] to [9], which is used in an open-air recording apparatus.

Preferred embodiments of the present invention are described in detail below.
<Aqueous inkjet composition>
By the way, among various disperse dyes, C.I. I. Although Disperse Red 60 has features such as excellent color developability, it has the following problems. That is, C.I. I. Conventionally, when Disperse Red 60 was used as a constituent component of an aqueous inkjet composition, the storage stability of the aqueous inkjet composition could not be sufficiently improved, and foreign matter was observed during long-term storage. In addition, problems such as clogging of head filters and nozzles during ejection by the ink jet method have occurred remarkably.

Therefore, the inventor of the present invention proposed C.I. I. Intensive research was conducted with the aim of providing an aqueous inkjet composition that can effectively prevent the occurrence of the above-described problems while making the most of the features of Disperse Red 60.
As a result, the present invention was achieved.

That is, the aqueous inkjet composition of the present invention contains C.I. I. Disperse Red 60, a compound represented by the following formula (1), a compound represented by the following formula (2), an ethylene oxide adduct of tristyrylphenol, and a derivative of an ethylene oxide adduct of tristyrylphenol. and an anionic dispersant.

（式（１）中、Ｒ^１は、炭素数が６以下の炭化水素基、または－（ＣＨ_２）_ｍ－ＮＲ^８Ｒ^９（ただし、ｍは６以下の整数、Ｒ^８、Ｒ^９は、それぞれ独立に、水素原子または炭素数が６以下の炭化水素基）であり、ｎは１以上の整数である。）

(In formula (1), R ¹ is a hydrocarbon group having 6 or less carbon atoms, or —(CH ₂ ) _m —NR ⁸ R ⁹ (where m is an integer of 6 or less, and R ⁸ and R ⁹ are each independently a hydrogen atom or a hydrocarbon group having 6 or less carbon atoms), and n is an integer of 1 or more.)

（式（２）中、Ｒ^２、Ｒ^３のうちの一方は－ＯＨであり、他方は－ＮＲ^４Ｒ^５（だだし、Ｒ^４、Ｒ^５は、それぞれ独立に、水素原子または炭素数が６以下の炭化水素基である。）であり、ｎは１以上の整数である。）

(In formula (2), one of R ² and R ³ is —OH, and the other is —NR ⁴ R ⁵ (provided that R ⁴ and R ⁵ are each independently a hydrogen atom or a is a hydrocarbon group of 6 or less), and n is an integer of 1 or more.)

With such a structure, the C.I. I. While obtaining the effect of including Disperse Red 60, there is a noticeable occurrence of foreign matter (especially crystalline foreign matter at the gas-liquid interface) due to long-term storage, and clogging of head filters and nozzles occurs during ejection by the inkjet method. It is possible to provide a water-based inkjet composition that is resistant to water.

On the other hand, satisfactory results cannot be obtained if the above conditions are not satisfied.
For example, when the above substance A was not used, C.I. I. The dispersion stability of Disperse Red 60 cannot be ensured, and foreign substances are likely to occur during long-term storage of the aqueous inkjet composition.

Further, when no anionic dispersant is used, or when other dispersants (e.g., nonionic dispersants, cationic dispersants, etc.) are used instead of the anionic dispersant, the water-based inkjet composition C.C. I. The dispersion stability of Disperse Red 60 cannot be ensured, and foreign substances are likely to occur during long-term storage of the aqueous inkjet composition.

In this specification, the term "aqueous inkjet composition" is a concept that includes not only the ink itself that is ejected by the inkjet method, but also the stock solution used for preparing the ink. In other words, the aqueous inkjet composition of the present invention may be directly ejected by an inkjet method, or may be ejected by an inkjet method after treatment such as dilution. good.

[Substance A]
The aqueous inkjet composition of the present invention comprises a compound represented by the above formula (1), a compound represented by the above formula (2), an ethylene oxide adduct of tristyrylphenol, and a derivative of an ethylene oxide adduct of tristyrylphenol. contains substance A, which is at least one compound selected from the group consisting of

The substance A is C.I. I. When used in combination with Disperse Red 60 and an anionic dispersant, C.I. I. The dispersion stability of Disperse Red 60 in the water-based inkjet composition and the storage stability of the water-based inkjet composition can be made excellent. It is possible to effectively prevent the occurrence of clogging of the head filter and nozzles. As a result, the water-based inkjet composition can be discharged stably over a long period of time, and the quality of the recorded matter obtained by the inkjet method can be stably improved. Further, the substance A is a component that hardly causes adverse effects on the quality of printed matter and sublimation printing.

The aqueous inkjet composition of the present invention may contain one type of compound as the substance A, or may contain a plurality of types of compounds. More specifically, substance A may be, for example, a mixture of a compound represented by formula (1) and a compound represented by formula (2).

The content of Substance A in the aqueous inkjet composition is preferably 0.05% by mass or more and 8.0% by mass or less, more preferably 0.07% by mass or more and 6.0% by mass or less. , more preferably 0.08% by mass or more and 5.0% by mass or less.

As a result, the storage stability of the water-based inkjet composition is further improved, and the generation of foreign substances during long-term storage is more effectively prevented.

In particular, when the aqueous inkjet composition is the ink itself that is ejected by an inkjet method, the content of the substance A in the ink is preferably 0.05% by mass or more and 4.5% by mass or less. It is more preferably 0.07% by mass or more and 3.0% by mass or less, and even more preferably 0.08% by mass or more and 2.0% by mass or less.

Further, when the aqueous inkjet composition is a stock solution used for preparing an ink to be ejected by an inkjet method, the content of the substance A in the stock solution is 0.5% by mass or more and 8.0% by mass or less. , more preferably 0.75% by mass or more and 6.0% by mass or less, and even more preferably 1.0% by mass or more and 5.0% by mass or less.

When the substance A constituting the water-based inkjet composition contains a plurality of types of compounds, the content rate is the sum of the content rates of these plurality of types of compounds.

[Anionic dispersant]
The aqueous inkjet composition of the present invention contains an anionic dispersant.

The anionic dispersant is not particularly limited as long as it ionizes to form an anion, but at least one of a compound represented by the following formula (3), a sodium salt of naphthalenesulfonic acid formalin condensate, and lignosulfonic acid is preferred.

（式（３）中、Ｒ^６は、炭素数が４以下の炭化水素基であり、ｎは１以上の整数である。）

(In formula ( ³ ), R6 is a hydrocarbon group having 4 or less carbon atoms, and n is an integer of 1 or more.)

This improves the hydrophobicity of the dispersant, and the C.I. I. The adsorption of the dispersant to Disperse Red 60 is promoted, and the long-term stability of the water-based inkjet composition is further improved.

R ⁶ in formula (3) may be a hydrocarbon group having 4 or less carbon atoms, but is preferably a hydrocarbon group having 2 or less carbon atoms (methyl group, ethyl group).

Thereby, the balance between the hydrophobicity and the hydrophilicity of the anionic dispersant can be made more suitable, and the C.I. I. The dispersion stability of Disperse Red 60 can be made more excellent.

The weight average molecular weight Mw of the anionic dispersant is preferably 1,000 to 20,000, more preferably 2,000 to 10,000, even more preferably 3,000 to 5,000.

As a result, the storage stability of the water-based inkjet composition is further improved, and the generation of foreign substances during long-term storage is more effectively prevented.

The aqueous inkjet composition may contain two or more compounds as anionic dispersants.

The content of the anionic dispersant in the aqueous inkjet composition is preferably 0.1% by mass or more and 30% by mass or less, more preferably 0.2% by mass or more and 25% by mass or less. 0.3% by mass or more and 20% by mass or less is more preferable.

As a result, the storage stability of the water-based inkjet composition is further improved, and the generation of foreign substances during long-term storage is more effectively prevented.

In particular, when the aqueous inkjet composition is the ink itself that is ejected by an inkjet method, the content of the anionic dispersant in the ink is preferably 0.1% by mass or more and 20% by mass or less. 0.2 mass % or more and 15 mass % or less is more preferable, and 0.3 mass % or more and 10 mass % or less is even more preferable.

Further, when the aqueous inkjet composition is a stock solution used for preparing an ink to be ejected by an inkjet method, the content of the anionic dispersant in the stock solution is 5.0% by mass or more and 30% by mass or less. , more preferably 8.0% by mass or more and 25% by mass or less, and even more preferably 12% by mass or more and 20% by mass or less.

When the anionic dispersant constituting the aqueous inkjet composition contains a plurality of types of compounds, the content rate is the sum of the content rates of the plurality of types of compounds.

[C. I. Disperse Red 60]
The aqueous inkjet composition contains C.I. I. Contains Disperse Red 60.

C.I. I. The average particle size of Disperse Red 60 is preferably 50 nm or more and 300 nm or less, more preferably 75 nm or more and 250 nm or less, and even more preferably 100 nm or more and 200 nm or less.

As a result, the storage stability of the water-based inkjet composition is further improved, and the generation of foreign substances during long-term storage is more effectively prevented. In addition, the recording area formed using the water-based inkjet composition can be sublimated more effectively, and the composition can be suitably applied to sublimation printing.

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

C. I. Commercially available products of Disperse Red 60 include, for example, PLATREAD 8375 (manufactured by Arimoto Chemical Industry Co., Ltd.).

C.I. I. The content of Disperse Red 60 is preferably 0.1% by mass or more and 30% by mass or less, more preferably 2.0% by mass or more and 25% by mass or less, and 5.0% by mass or more and 20% by mass. More preferably:

As a result, a higher color density can be obtained in the recording area formed using the water-based inkjet composition, the storage stability of the water-based inkjet composition is further improved, and foreign matter is generated during long-term storage. is more effectively prevented.

C.I. I. When the content of Disperse Red 60 is XD [% by mass] and the content of substance A is XA [% by mass], it is preferable to satisfy the relationship of 0.002≦XA/XD≦1.5. It more preferably satisfies the relationship 03≤XA/XD≤0.8, and further preferably satisfies the relationship 0.05≤XA/XD≤0.5.

As a result, the storage stability of the water-based inkjet composition is further improved, and the generation of foreign substances during long-term storage is more effectively prevented.

C.I. I. When the content of Disperse Red 60 is XD [mass%] and the content of anionic dispersant is XB [mass%], it is preferable to satisfy the relationship of 0.4 ≤ XB / XD ≤ 2.0, It is more preferable to satisfy the relationship of 0.5≤XB/XD≤1.5, and more preferably to satisfy the relationship of 0.6≤XB/XD≤1.2.

As a result, the storage stability of the water-based inkjet composition is further improved, and the generation of foreign substances during long-term storage is more effectively prevented.

A relationship of 0.002 ≤ XA/XB ≤ 1.5, where XA [mass%] is the content of the substance A and XB [mass%] is the content of the anionic dispersant in the aqueous inkjet composition. is preferably satisfied, more preferably 0.03≤XA/XB≤0.8, and even more preferably 0.05≤XA/XB≤0.5.

As a result, the storage stability of the water-based inkjet composition is further improved, and the generation of foreign substances during long-term storage is more effectively prevented.

[water]
Aqueous inkjet compositions contain water.

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. More preferably, it is at least 75% by mass or less.

As a result, the viscosity of the water-based 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 aqueous inkjet composition may contain a solvent other than water.

This makes it possible to suitably adjust the viscosity of the aqueous inkjet composition and enhance the moisturizing properties of the aqueous inkjet composition. As a result, it is possible to more stably discharge droplets by the inkjet method.

Solvents other than water contained in the aqueous inkjet composition include, for example, glycerin, propylene glycol, 2-pyrrolidone, and the like.

By containing these solvents, it is possible to reduce the evaporation rate due to excellent moisturizing ability, and to perform more stable droplet ejection.

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 preferable that the content is not less than 40% by mass.
As a result, the effect of containing the solvent other than water described above is exhibited more remarkably.

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

Thereby, the wettability of the water-based inkjet composition to the recording medium (substrate) can be made more suitable, which is advantageous in obtaining better image quality.

Various surfactants such as anionic surfactants, cationic surfactants, and nonionic surfactants can be used as the surfactant contained in the aqueous inkjet composition.

More specifically, examples of the surfactant contained in the aqueous inkjet composition include acetylenic surfactants, silicone surfactants, fluorine surfactants, and the like.

When the aqueous inkjet composition contains a silicone-based surfactant, the wettability of the aqueous inkjet composition to the recording medium (substrate) can be further improved, and an image with better gradation can be obtained. (recording portion) 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 C.I. I. Disperse Red 60: With respect to 100 parts by mass, it is preferably 5.0 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, 10 parts by mass or more and 70 parts by mass Part or less is more preferable.

As a result, the effect of containing the silicone-based surfactant described above is exhibited more remarkably.

Examples of commercially available silicone 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 BYK-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 (all trade names, manufactured by Shin-Etsu Chemical Co., Ltd.).

[Other ingredients]
The aqueous inkjet composition may contain components (other components) other than the components described above.

Other components include, for example, C.I. I. Coloring agents other than Disperse Red 60, dispersing agents other than the above, triethylene glycol monomethyl ether, triethylene glycol monobutyl ether, diethylene glycol monomethyl ether, 1,2-hexanediol, 1,2-pentanediol, 1,2-butanediol , 3-methyl-1,5-pentanediol, pH adjusters, chelating agents such as ethylenediaminetetraacetate (EDTA), preservatives/antifungal agents, rust inhibitors, and the like. As an antiseptic/antifungal agent, for example, a compound having an isothiazoline ring structure in the molecule can be preferably used.

The content of other components (the sum of the contents when multiple components are included as other components) is preferably 6% by mass or less, more preferably 5% 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. , 3% by mass or less.

The surface tension of the aqueous inkjet composition at 25° 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, the clogging of the nozzles of the ejection device of the inkjet system is less likely to occur, and the ejection stability of the water-based inkjet composition is further improved. Also, even if the nozzles are clogged, it is possible to improve the recoverability by capping the nozzles.

As the surface tension, a value measured by the Wilhelmy method can be used. Surface tension can be measured using a surface tensiometer (eg, CBVP-7 manufactured by Kyowa Interface Science Co., Ltd.).

The viscosity of the aqueous inkjet composition at 25° 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 more preferable to have
This further improves the ejection stability of the aqueous inkjet composition.

The viscosity was measured by increasing the shear rate from 10 [s ^-1 ] to 1000 [s ^-1 ] using a viscoelasticity tester (eg, MCR-300 manufactured by Pysica) at 25 ° 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 apparatus using an inkjet method in a state of being housed in a container such as a cartridge, bag, tank, or the like. In other words, the recording apparatus according to the present invention comprises a container (ink cartridge, etc.) for containing 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 apparatus for ejecting droplets is not limited. The composition for inkjet can be used in an open-air recording apparatus (more specifically, for example, an inkjet including an ink container having an ink inlet capable of replenishing ink and a recording head having a nozzle hole for ejecting the ink). It is preferably one (including undiluted solution) that is applied to a recording device).

In such a recording apparatus, C.I. I. When an ink containing Disperse Red 60 is applied, there is a problem that foreign matter (especially crystalline foreign matter) is likely to occur at the gas-liquid interface due to contact of the ink with the atmosphere. Therefore, even if it is applied to such a recording apparatus, it is possible to effectively prevent the above problems from occurring. In other words, the effect of the present invention is exhibited more remarkably when it is applied to an atmospheric open type recording apparatus.

<Recording method>
The aqueous inkjet composition of the present invention can be applied, for example, to direct printing, thermal transfer printing (eg, sublimation textile printing), and the like. I. Since Disperse Red 60 has sublimation properties, it can be suitably applied to the thermal transfer printing method.

An example of a thermal transfer printing method (sublimation textile printing) will be described below as a recording method using the aqueous ink jet composition of the present invention.

The recording method according to the present embodiment comprises an ink deposition step of depositing an aqueous inkjet composition on an intermediate transfer medium by an inkjet method, and heating the intermediate transfer medium to which the aqueous inkjet composition has been deposited, followed by heating the aqueous inkjet composition. C.I. as a sublimation dye contained in products. I. and a transfer step of transferring the Disperse Red 60 onto a recording medium.

[Ink adhesion process]
In the ink application step, the aqueous inkjet composition is applied to the intermediate transfer medium by an inkjet method. The aqueous inkjet composition can be ejected by an inkjet method using a known inkjet recording apparatus. As an ejection method, a piezo method, a method in which ink is ejected using bubbles generated by heating ink, or the like can be used. Among them, the piezo method is preferable from the viewpoint of difficulty in deterioration of the composition for water-based inkjet.

In the ink application step, inks other than the water-based 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 dedicated ink-jet paper, coated paper, etc.), or the like can be used. Among them, paper provided with an ink-receiving layer made of inorganic fine particles such as silica is preferable. This makes it possible to obtain an intermediate transfer medium in which bleeding or the like is suppressed in the process of drying the water-based inkjet composition adhering to the intermediate transfer medium. I. Sublimation of Disperse Red 60 tends to proceed more smoothly.

[Transfer process]
After that, the intermediate transfer medium to which the aqueous inkjet composition has been applied is heated, and C.I. I. Disperse Red 60 is transferred onto a recording medium. A recorded matter is thus obtained.

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 transfer can be further reduced, and the productivity of printed matter can be further improved. In addition, it is possible to further improve the color developability of the obtained recorded matter.

The heating time in this step is preferably 30 seconds or more and 90 seconds or less, 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 transfer can be further reduced, and the productivity of printed matter can be further improved. In addition, it is possible to further improve the color developability of the obtained recorded matter.

In addition, this step may be performed by heating the surface of the intermediate transfer medium to which the aqueous inkjet composition is adhered while facing the recording medium at a constant distance, or by heating the surface of the recording medium. Although the heating may be carried out while they are in close contact with each other, it is preferable to carry out the heating while the surface of the intermediate transfer medium to which the water-based inkjet composition has adhered is in close contact with the surface of the recording medium.

As a result, the energy required for transfer can be further reduced, and the productivity of printed matter can be further improved. In addition, it is possible to further improve the color developability of the obtained recorded matter.

[recoding media]
Examples of the recording medium include, but are not limited to, cloth (hydrophobic fiber cloth, etc.), resin (plastic) film, paper, glass, metal, and ceramics. Moreover, as a recording medium, a material having a three-dimensional shape such as a sheet shape, a spherical shape, a rectangular parallelepiped shape, or the like may be used.

When the recording medium is cloth, examples of fibers constituting the cloth include polyester fiber, nylon fiber, triacetate fiber, diacetate fiber, polyamide fiber, and blended products using two or more of these fibers. . Also, a blended product of these with regenerated 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 polyamideimide film.

The resin (plastic) film may be a laminate in which a plurality of layers are laminated, or may be composed of a gradient material whose composition changes in a gradient manner.

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

For example, the aqueous inkjet composition of the present invention may be used for ejection in an inkjet system, and may not be applied to the above-described recording methods.

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

In this case, the pretreatment step includes, for example, a step of applying a coat layer to the recording medium.

Further, the intermediate processing step includes, for example, a step of preheating the recording medium.
Further, the post-processing step includes, for example, a step of washing the recording medium.

Further, the water-based 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 attaching an aqueous inkjet composition to an ink-receiving layer of a recording medium (film product, etc.) provided with a peelable ink-receiving layer by an inkjet method; A step of heating a recording medium provided with an ink-receiving layer to which an aqueous inkjet composition is adhered as it is, and performing sublimation diffusion dyeing from the ink-receiving layer to the recording medium on the lower layer side, and peeling the ink-receiving layer from the recording medium. and obtaining a recorded matter.

Next, specific examples of the present invention will be described.
[1] Preparation of Stock Solution for Inkjet Ink Production (Aqueous Inkjet Composition) (Example A1)
First, C.I. I. Disperse Red 60, an ethylene oxide adduct of tristyrylphenol as substance A (a substance in which R ⁷ in formula (4) is H), and a methylnaphthalenesulfonic acid formalin condensate Na as an anionic dispersant (formula A substance in (3) in which R ⁶ is —CH ₃ ) and pure water were mixed at the ratio shown in Table 3, and stirred at 3000 rpm with a high shear mixer (manufactured by Silverson) to form a slurry. . Thereafter, the prepared slurry and glass beads with a diameter of 0.5 mm were stirred and dispersed in a bead mill (LMZ015 Ashizawa Fine Tech Co., Ltd.) under water cooling to prepare an inkjet ink manufacturing stock solution as a water-based inkjet composition.

C.I. I. The average particle size of Disperse Red 60 was 150 nm.

(Examples A2 to A21)
A water-based inkjet composition was prepared in the same manner as in Example A1, except that the types of substance A and anionic dispersant, and the blending ratio of each component were as shown in Tables 1, 2, 3, and 4. A stock solution for inkjet ink production was produced.

(Comparative Examples A1 to A6)
A water-based inkjet composition was prepared in the same manner as in Example A1 except that the types of the disperse dye, the substance A and the anionic dispersant, and the compounding ratio of each component were as shown in Tables 1, 2, and 4. A stock solution for inkjet ink production was produced.

Table 1 shows the relationship between the abbreviations of the substance A and the conditions used in the preparation of the aqueous inkjet compositions (stock solutions for producing inkjet inks) of each of the above Examples and Comparative Examples. are shown in Table 2, and Tables 3 and 4 show the compositions of the water-based inkjet compositions (undiluted liquids for producing inkjet inks) of the respective Examples and Comparative Examples. In the table, C.I. I. Disperse Red 60 as "DR60", C.I. I. Disperse Red 153 as "DR153", C.I. I. "DR167" for Disperse Red 167, "A1'" for a polycarboxylic acid-based activator (manufactured by Sanyo Chemical Industries, Ltd., Caribon L-400), and polyoxy as a dispersant (nonionic dispersant) other than an anionic dispersant Ethylene sorbitan fatty acid ester (Solbon T-40 manufactured by Toho Chemical Co., Ltd.) is indicated as "B1'". A3 as the substance A used in Example A3 and the like is represented by the following formula (5). In addition, each of the stock solutions for inkjet ink production of Examples A1 to A21 has a viscosity within the range of 2.0 mPa·s or more and 30 mPa·s or less, and a surface tension of 25 mN/m or more and 60 mN/m or less. was within the range of The viscosity was measured by increasing the shear rate from 10 [s ^-1 ] to 1000 [s ^-1 ] at 25 ° C. using a viscoelasticity tester MCR-300 (manufactured by Pysica). It was measured by reading the viscosity at time. The surface tension was measured by the Wilhelmy method at 25° C. using a surface tensiometer (CBVP-7, manufactured by Kyowa Interface Science Co., Ltd.).

[2] Evaluation of stock solution for inkjet ink production [2-1] Storage stability (particle size change)
Regarding the water-based inkjet compositions (undiluted liquids for inkjet ink production) of each of the above Examples and Comparative Examples, the average particle size of the disperse dye immediately after production and the average particle diameter were placed in a predetermined container and allowed to stand in an environment of 60° C. for 1 week. The average particle size of the disperse dye at the time of production is determined, and from these values, the variation rate of the average particle size of the disperse dye when left in an environment of 60 ° C. for one week with respect to the average particle size of the disperse dye immediately after production is determined. , was evaluated according to the following criteria. Microtrac UPA (manufactured by Nikkiso Co., Ltd.) was used for the measurement of the average particle size.

A: Variation rate of average particle size is less than 3%.
B: Variation rate of average particle size is 3% or more and less than 5%.
C: Variation rate of average particle size is 5% or more and less than 7%.
D: Variation rate of average particle size is 7% or more and less than 10%.
E: Variation rate of average particle diameter is 10% or more.

[2-2] Status of generation of foreign matter 10 mL of each of the water-based inkjet compositions (undiluted liquids for inkjet ink production) of each of the above examples and comparative examples is placed in a predetermined glass bottle, and a gas-liquid interface exists. and left for 5 days in an environment of 60°C. Then, the aqueous inkjet composition (stock solution for inkjet ink production) is filtered through a metal mesh filter (10 μm in diameter), and the number of solids remaining on the metal mesh filter is counted per 1 mm square according to the following criteria. evaluated.

A: The number of solids per 1 mm square was less than 5.
B: The number of solids per 1 mm square was 5 or more and less than 20.
C: The number of solids per 1 mm square was 20 or more and less than 30.
D: The number of solids per 1 mm square was 30 or more and less than 50.
E: The number of solids per 1 mm square was 50 or more.
These results are summarized in Table 5.

As can be seen from Table 5, the present invention produced excellent results. On the other hand, in Comparative Examples, satisfactory results were not obtained.

[3] Preparation of inkjet ink (aqueous inkjet composition) (Example B1)
Table 6 shows the stock solution for inkjet ink production prepared in Example A1, glycerin, 2-pyrrolidone, propylene glycol, BYK348 (manufactured by BYK-Chemie Japan) as a silicone surfactant, and pure water. An inkjet ink as a water-based inkjet composition was produced by mixing at the indicated ratio and stirring at 3000 rpm with a high shear mixer (manufactured by Silverson).

C.I. in inkjet ink I. The average particle size of Disperse Red 60 was 150 nm.

(Examples B2 to B19)
Aqueous inkjet ink was prepared in the same manner as in Example B1, except that the types of stock solutions for inkjet ink production were as shown in Tables 6 and 7, and the blending ratio of each component was as shown in Tables 6 and 7. An inkjet ink as a composition was produced.

(Comparative Examples B1 to B6)
An inkjet ink as a water-based inkjet composition was prepared in the same manner as in Example B1 except that the type of stock solution for inkjet ink production was as shown in Table 7 and the blending ratio of each component was as shown in Table 7. manufactured.

Tables 6 and 7 collectively show the conditions of the water-based inkjet compositions (inkjet inks) of the above Examples and Comparative Examples. In the table, "Gly" for glycerin, "2-Py" for 2-pyrrolidone, "PG" for propylene glycol, "BYK348" for BYK348 (manufactured by BYK-Chemie Japan) as a silicone-based surfactant, and "BYK348" for acetylene-based Olfine EXP4300 (manufactured by Nissin Chemical Industry Co., Ltd.) as a surfactant was indicated as "EXP4300". The inkjet inks of Examples B1 to B19 all have viscosities in the range of 2.0 mPa·s or more and 10 mPa·s or less, and surface tensions in the range of 25 mN/m or more and 35 mN/m or less. was the value of The viscosity was measured by increasing the shear rate from 10 [s ^-1 ] to 1000 [s ^-1 ] at 25 ° C. using a viscoelasticity tester MCR-300 (manufactured by Pysica). It was measured by reading the viscosity at time. The surface tension was measured by the Wilhelmy method at 25° C. using a surface tensiometer (CBVP-7, manufactured by Kyowa Interface Science Co., Ltd.).

[4] Evaluation of inkjet ink [4-1] Storage stability (particle size change)
Regarding the water-based inkjet compositions (inkjet inks) of each of the above Examples and Comparative Examples, the average particle diameter of the disperse dye immediately after production and the average particle size of the disperse dye after being placed in a predetermined ink container and left for one week in an environment of 60 ° C. The average particle size of the disperse dye is determined, and from these values, the variation rate of the average particle size of the disperse dye when left in an environment of 60 ° C. for one week with respect to the average particle size of the disperse dye immediately after production is determined, Evaluation was made according to the following criteria. Microtrac UPA (manufactured by Nikkiso Co., Ltd.) was used for the measurement of the average particle size.

A: Variation rate of average particle size is less than 3%.
B: Variation rate of average particle size is 3% or more and less than 5%.
C: Variation rate of average particle size is 5% or more and less than 7%.
D: Variation rate of average particle size is 7% or more and less than 10%.
E: Variation rate of average particle diameter is 10% or more.

[4-2] State of generation of foreign matter 10 mL of each of the water-based inkjet compositions (inkjet inks) of each of the above examples and comparative examples was placed in a predetermined glass bottle, and in the presence of a gas-liquid interface, ℃ environment for 5 days. Thereafter, the aqueous inkjet composition (inkjet ink) was filtered through a metal mesh filter (10 μm diameter), and the number of solids remaining on the metal mesh filter was counted per 1 mm square and evaluated according to the following criteria.

A: The number of solids per 1 mm square was less than 5.
B: The number of solids per 1 mm square was 5 or more and less than 20.
C: The number of solids per 1 mm square was 20 or more and less than 30.
D: The number of solids per 1 mm square was 30 or more and less than 50.
E: The number of solids per 1 mm square was 50 or more.

[4-3] Ejection stability by inkjet method Each of the water-based inkjet compositions (inkjet inks) of the above examples and comparative examples was filled in a predetermined ink storage container and left in an environment of 60 ° C. for 5 days. did.

After that, the storage container is mounted on a recording device PX-H6000 (manufactured by Seiko Epson), the inkjet ink is discharged, and a solid image is printed on the intermediate transfer medium TRANSJET Classic (manufactured by Cham Paper) at a recording resolution of 1440 × 720 dpi. A pattern was attached. The operating environment of the recording apparatus (printer) was 40° C. and 20 RH%.

The number of missing nozzles when solid patterns were recorded on 30 sheets of an intermediate transfer medium was examined and evaluated according to the following criteria.

A: The number of missing nozzles was zero.
B: The number of missing nozzles was 1 or more and 9 or less.
C: The number of missing nozzles was 10 or more and 19 or less.
D: The number of missing nozzles was 20 or more and 29 or less.
E: The number of missing nozzles was 30 or more.

The PX-H6000 ink storage container manufactured by Seiko Epson Corporation (the ink storage container described above) is equipped with an ink inlet capable of replenishing the water-based inkjet composition, and when installed in the recording apparatus in the state of use, It is open to the atmosphere.

[4-4] Clogging recovery property Each of the water-based inkjet compositions (inkjet inks) of the above examples and comparative examples is filled in a predetermined ink container, and the container is placed in a recording apparatus PX-H6000. (manufactured by Seiko Epson).

After confirming that all the nozzles ejected normally, the recording apparatus was turned off in a normal state, and left in an environment of 40° C. for two months.

After that, the number of recovery operations by suction required to achieve normal ejection was determined and evaluated according to the following criteria.

A: Clean ejection was started immediately after the power was turned on.
B: Normalized after 1-2 recovery operations.
C: Normalized after 3 to 4 recovery operations.
D: Normalized after 5 to 6 recovery operations.
E: Did not recover after 6 recovering actions.

[4-5] Color development (OD value)
The water-based inkjet composition side of the 30th intermediate transfer medium to which the inkjet ink has been applied in [4-3] above is brought into close contact with the fabric (100% polyester, Amina, manufactured by Toray Industries, Inc.) that is a white recording medium. In this state, a heat press (TP-608M, manufactured by Taiyo Seiki Co., Ltd.) was used to heat at 180° C. for 60 seconds to perform sublimation transfer to obtain each recorded material.

Each recorded matter obtained was evaluated for color development. Specifically, the OD value of each recorded matter obtained was measured using a colorimeter (Gretag Macbeth Spectrolino, manufactured by X-Rite) and evaluated according to the following criteria.

A: OD value is 1.50 or more.
B: OD value is 1.45 or more and less than 1.50.
C: OD value is 1.40 or more and less than 1.45.
D: OD value is 1.35 or more and less than 1.40.
E: OD value is less than 1.35.
These results are summarized in Table 8.

As can be seen from Table 8, the present invention provided excellent results. On the other hand, in Comparative Examples, satisfactory results were not obtained.

Claims (10)

C. I. Disperse Red 60;
A group consisting of a compound represented by the following formula (1), a compound represented by the following formula (2), an ethylene oxide adduct of tristyrylphenol, and a derivative of an ethylene oxide adduct of tristyrylphenol represented by the following formula (4). a substance A that is at least one compound selected from
and an anionic dispersant.

(In formula (1), R ¹ is a hydrocarbon group having 6 or less carbon atoms, or —(CH ₂ ) _m —NR ⁸ R ⁹ (where m is an integer of 6 or less, and R ⁸ and R ⁹ are each independently a hydrogen atom or a hydrocarbon group having 6 or less carbon atoms), and n is an integer of 1 or more.)

(In formula (2), one of R ² and R ³ is —OH, and the other is —NR ⁴ R ⁵ (provided that R ⁴ and R ⁵ are each independently a hydrogen atom or a is a hydrocarbon group of 6 or less), and n is an integer of 1 or more.)

(In formula (4), R ⁷ is —SO ₃ H.) 2. The aqueous inkjet composition according to claim 1, wherein the anionic dispersant is at least one of a compound represented by the following formula (3), a sodium salt of naphthalenesulfonic acid formalin condensate, and ligninsulfonic acid.

(In formula ( ³ ), R6 is a hydrocarbon group having 4 or less carbon atoms, and n is an integer of 1 or more.) The above C.I. I. 2. Satisfying a relationship of 0.002≦XA/XD≦1.5, where XD [mass %] is the content of Disperse Red 60 and XA [mass %] is the content of substance A. 3. The aqueous inkjet composition according to . The above C.I. I. 1. Satisfying the relationship of 0.4≦XB/XD≦2.0, where XD [mass %] is the content of Disperse Red 60 and XB [mass %] is the content of the anionic dispersant. 4. The composition for aqueous inkjet according to any one of 1 to 3. 1. Satisfying the relationship of 0.002≦XA/XB≦1.5, where XA [mass %] is the content of the substance A and XB [mass %] is the content of the anionic dispersant. 5. The composition for water-based inkjet according to any one of 1 to 4. The above C.I. I. 6. The aqueous inkjet composition according to any one of claims 1 to 5, wherein the content of Disperse Red 60 is 0.1% by mass or more and 30% by mass or less. 7. The aqueous inkjet composition according to any one of claims 1 to 6, wherein the content of the substance A is 0.05% by mass or more and 8.0% by mass or less. 8. The aqueous inkjet composition according to any one of claims 1 to 7, wherein the content of the anionic dispersant is 0.1% by mass or more and 30% by mass or less. 9. The aqueous inkjet composition according to any one of claims 1 to 8, wherein the anionic dispersant has a weight average molecular weight of 1000 or more and 20000 or less. 10. The water-based inkjet composition according to any one of claims 1 to 9, which is used in an open-air recording apparatus.