Textile inkjet ink composition

Abstract

To provide a textile inkjet ink composition with excellent color development, intermittent discharge characteristics, and friction resistance.SOLUTION: A textile inkjet ink composition of the present invention is an ink composition comprising an acid dye, a water-soluble organic solvent, and water, wherein the acid dye includes one or more kinds selected from the group consisting of C.I. Acid Black 172 and C.I. Acid Black 52:1, wherein a content of the acid dye is 10.0 mass% or more relative to the total amount of the ink composition, and the water-soluble organic solvent comprises a linear alkyl diol having a carbon number of 2 or more and 5 or less and having hydroxyl groups at both terminals, and a glycol ether compound having a standard boiling point of 220°C or more and 290°C or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an ink-jet printing ink composition. [Background technology]

[0002] Inkjet recording methods are not only used to record images on media such as paper, but also to print fabrics, and various ink compositions for inkjet printing are being investigated. For example, Patent Document 1 describes an inkjet ink composition that contains an acid dye including CI Acid Black 172 and / or CI Acid Black 52:1, an organic solvent including N-hydroxyethylpyrrolidone and N-vinyl-2-pyrrolidone, and water. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-155668 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, an ink-jet ink composition containing CI Acid Black 172 and / or CI Acid Black 52:1 as an acid dye has a problem that if the content of these acid dyes is high, the intermittent ejection characteristics and abrasion resistance are poor, whereas if the content of these acid dyes is low in the ink-jet ink composition, the color development is poor. [Means for solving the problem]

[0005] The present invention is an ink composition for textile printing, comprising an acid dye, a water-soluble organic solvent, and water, wherein the acid dye comprises one or more selected from the group consisting of CI Acid Black 172 and CI Acid Black 52:1, the content of the acid dye is 10.0 mass % or more relative to the total amount of the ink composition, and the water-soluble organic solvent comprises a linear alkyl diol having 2 to 5 carbon atoms and having hydroxy groups at both ends, and a glycol ether compound having a normal boiling point of 220° C. or more and 290° C. or less. [Brief description of the drawings]

[0006] [Figure 1] 1 is a flowchart illustrating an example of an inkjet recording method. [Diagram 2] Table 1 shows the composition of the inkjet ink composition. [Diagram 3] Table 2 shows the composition of the inkjet ink composition. [Figure 4] Table 3 shows the evaluation results. [Diagram 5] Table 4 shows the evaluation results. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Below, we will explain in detail the embodiment of the present invention (hereinafter referred to as the "present embodiment"). However, the present invention is not limited to this embodiment, and various modifications are possible without departing from the gist of the present invention.

[0008] 1. Textile inkjet ink composition The textile inkjet ink composition (hereinafter also referred to as "ink composition") of this embodiment is an ink composition containing an acid dye, a water-soluble organic solvent, and water, wherein the acid dye contains one or more selected from the group consisting of CI Acid Black 172 and CI Acid Black 52:1, the content of the acid dye is 10.0 mass % or more with respect to the total amount of the ink composition, and the water-soluble organic solvent contains a linear alkyl diol having 2 to 5 carbon atoms and having hydroxy groups at both ends, and a glycol ether compound having a normal boiling point of 220°C to 290°C.

[0009] According to this embodiment, it is possible to obtain an ink composition having excellent color development, intermittent ejection characteristics, and abrasion resistance.

[0010] Although it is not clear why such excellent effects are obtained according to this embodiment, the inventors presume as follows.

[0011] That is, an ink composition containing CI Acid Black 172 and / or CI Acid Black 52:1 as an acid dye can produce a good black color when the content of these acid dyes is 10.0 mass % or more relative to the total amount of the ink composition. However, if the content of the acid dye is 10.0% by mass or more, the acid dye aggregates in the ink composition, and the ink composition thickens when the ink is dried, so that the intermittent ejection characteristics tend to deteriorate. Furthermore, if the content of the acid dye is 10.0% by mass or more, the acid dye is less likely to penetrate into the recording medium and is more likely to aggregate on the surface of the recording medium, so that the acid dye is more likely to fall off from the recording medium. Therefore, the friction resistance also tends to decrease.

[0012] On the other hand, the ink composition of this embodiment contains, as the water-soluble organic solvent, a linear alkyl diol having 2 to 5 carbon atoms and hydroxy groups at both ends, and a glycol ether compound having a normal boiling point of 220° C. to 290° C. The glycol ether compound enhances the permeability of the ink composition into the recording medium, and allows the ink composition containing the acid dye to penetrate into the inside of the recording medium, so that the acid dye is less likely to aggregate on the surface of the recording medium and is less likely to fall off from the recording medium. Therefore, the ink composition of the present embodiment can provide excellent color development and excellent abrasion resistance.

[0013] On the other hand, it is difficult to suppress aggregation of the acid dye in the ink composition and thickening of the ink composition when the ink is dried using the glycol ether compound, and therefore, even if excellent color development and abrasion resistance can be obtained by only including the glycol ether compound as the water-soluble organic solvent, the intermittent ejection characteristics are insufficient.

[0014] In this regard, the ink composition of the present embodiment contains the linear alkyl diol together with the glycol ether compound. The linear alkyl diol has a carbon chain as a hydrophobic part, and the carbon chain is linear and has a length of 2 to 5 carbon atoms. The linear alkyl diol also has hydroxy groups at both ends of the carbon chain as a hydrophilic part. Therefore, the carbon chain of the linear alkyl diol can have affinity with the acid dye due to the hydrophobic effect while surrounding the hydrophobic part of the acid dye like a micelle structure. In addition, the hydroxy group, which is the hydrophilic part of the linear alkyl diol, has affinity with the glycol ether compound in the ink composition. Therefore, the linear alkyl diol can suppress the aggregation of the acid dyes by surrounding the acid dye, and can be suitably dissolved in the ink composition together with the acid dye. Even when the ink is dried, the thickening of the ink composition can be suitably suppressed. For this reason, it is presumed that the ink composition of the present embodiment can provide excellent color development and abrasion resistance, as well as excellent intermittent ejection characteristics. In addition, by using the linear alkyl diol, aggregation of the acid dye is suppressed, so that more excellent abrasion resistance tends to be obtained. However, the reason is not limited to this.

[0015] Next, each component contained in the ink composition will be described.

[0016] 1.1. Acid dye The ink composition of the present embodiment contains an acid dye. The acid dye includes at least one selected from the group consisting of CI Acid Black 172 and CI Acid Black 52:1. The acid dye may be used alone or in combination of two or more.

[0017] Since an ink composition having excellent color development, intermittent ejection characteristics, and abrasion resistance can be obtained, the content of the acid dye is 10.0% by mass or more relative to the total amount of the ink composition. Since an ink composition having better intermittent ejection characteristics and abrasion resistance color development and further excellent color development can be obtained, the content of the acid dye is preferably 10.5% by mass or more relative to the total amount of the ink composition. Since an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance can be obtained, the content of the acid dye is preferably 30.0% by mass or less relative to the total amount of the ink composition, more preferably 25.0% by mass or less, even more preferably 20.0% by mass or less, and even more preferably 15.0% by mass or less.

[0018] The acid dye preferably includes CI Acid Black 172 or CI Acid Black 52:1, since this provides an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance.

[0019] 1.2. Water-soluble organic solvents The ink composition includes a water-soluble organic solvent. The water-soluble organic solvent includes a linear alkyl diol having 2 to 5 carbon atoms and hydroxyl groups at both ends, and a glycol ether compound having a normal boiling point of 220° C. to 290° C. The water-soluble organic solvent may be used alone or in combination of two or more.

[0020] 1.2.1. Linear alkyl diol having 2 to 5 carbon atoms and hydroxyl groups at both ends The ink composition contains, as a water-soluble organic solvent, a linear alkyl diol having 2 to 5 carbon atoms and having hydroxy groups at both ends (hereinafter, also referred to as a "specific alkyl diol"). n H 2n+2 (n is an integer of 2 to 5), in which one hydrogen atom bonded to each of the two carbon atoms at both ends of a linear saturated hydrocarbon is substituted with a hydroxy group. The specific alkyl diol may be used alone or in combination of two or more kinds.

[0021] In this embodiment, by using a specific alkyldiol, there is a tendency to obtain an ink composition that has excellent intermittent ejection characteristics in addition to excellent color development and abrasion resistance.

[0022] Since an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance can be obtained, the specific alkyl diol preferably contains one or more selected from the group consisting of ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,5-pentanediol. Since an ink composition having better color development and abrasion resistance as well as better intermittent ejection characteristics can be obtained, the specific alkyl diol more preferably contains one or more selected from the group consisting of 1,3-propanediol and 1,4-butanediol, and even more preferably contains 1,3-propanediol.

[0023] In order to obtain an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance, the content of the specific alkyl diol is preferably 1.0% by mass or more and 20.0% by mass or less, more preferably 3.0% by mass or more and 17.0% by mass or less, and even more preferably 5.0% by mass or more and 15.0% by mass or less, relative to the total amount of the ink composition. In order to obtain an ink composition having better color development, abrasion resistance, and intermittent ejection characteristics, the content of the specific alkyl diol is even more preferably 7.0% by mass or more and 13.0% by mass or less, relative to the total amount of the ink composition.

[0024] 1.2.2. Glycol ether compounds with normal boiling points of 220°C or higher and 290°C or lower The ink composition contains, as a water-soluble organic solvent, a glycol ether compound (hereinafter referred to as a "specific glycol ether compound") having a normal boiling point (hereinafter also referred to as "BP") of 220°C or more and 290°C or less. In this specification, normal boiling point means the boiling point at a standard atmospheric pressure of 1013.25 hPa. In this specification, a glycol ether compound is a compound that has a hydroxy group in its structure and in which one hydroxy group of a glycol is etherified. The specific glycol ether compound may be used alone or in combination of two or more types.

[0025] In this embodiment, by using a specific glycol ether compound, the ink composition tends to have excellent color development and excellent abrasion resistance. In addition, additives such as surfactants tend to be suitably dissolved in the ink composition. Furthermore, the ink composition tends to have good permeability to the recording medium, good wettability to the head and flow path, and good antibacterial properties.

[0026] Specific glycol ether compounds include, for example, diethylene glycol monobutyl ether (BP: 231° C.), diethylene glycol monohexyl ether (BP: 259° C.), ethylene glycol monophenyl ether (BP: 245° C.), triethylene glycol monomethyl ether (BP: 248° C.), tripropylene glycol monomethyl ether (BP: 242° C.), diethylene glycol di-n-butyl ether (BP: 255° C.), tripropylene glycol monobutyl ether (BP: 271° C.), ethylene glycol monobenzyl ether (BP: 256° C.), triethylene glycol monobutyl ether (BP: 278° C.), tetraethylene glycol monobutyl ether (BP: 278° C.), triethylene glycol (BP: 287° C.), and polyethylene glycol monomethyl ether (BP: 290° C.).

[0027] Since an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance can be obtained, the specific glycol ether compound preferably includes one or more selected from the group consisting of diethylene glycol monobutyl ether and triethylene glycol monobutyl ether, and more preferably includes triethylene glycol monobutyl ether.

[0028] In order to obtain an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance, the content of the specific glycol ether compound is preferably 0.5% by mass or more and 15.0% by mass or less, more preferably 1.0% by mass or more and 10.0% by mass or less, and even more preferably 1.5% by mass or more and 7.0% by mass or less, based on the total amount of the ink composition. In order to obtain an ink composition having better color development, abrasion resistance, and intermittent ejection characteristics, the content of the specific glycol ether compound is even more preferably 2.0% by mass or more and 5.0% by mass or less, based on the total amount of the ink composition.

[0029] Since an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance can be obtained, the mass ratio of the specific alkyl diol to the specific glycol ether compound (specific alkyl diol / specific glycol ether compound) is preferably 1.0 to 12.0, more preferably 1.2 to 11.5, and even more preferably 1.5 to 7.5. Since an ink composition having better color development, abrasion resistance, and intermittent ejection characteristics can be obtained, the mass ratio (specific alkyl diol / specific glycol ether compound) is even more preferably 2.3 to 6.0, and even more preferably 2.5 to 5.0.

[0030] 1.3.Water The ink composition includes water. Examples of water include pure water such as ion-exchanged water, ultrafiltered water, reverse osmosis water, and distilled water, as well as ultrapure water from which ionic impurities have been removed as much as possible. Water sterilized by ultraviolet irradiation, addition of hydrogen peroxide, or the like is preferred because it can suppress the growth of mold and bacteria when the treatment liquid composition is stored for a long period of time.

[0031] The water content is preferably 30.0% by mass or more and 80.0% by mass or less based on the total amount of the ink composition. By setting the water content within this range, an increase in the viscosity of the ink composition can be suppressed.

[0032] 1.4. Lactam compounds The ink composition preferably further contains a lactam compound. The lactam compound may be used alone or in combination of two or more kinds.

[0033] In this embodiment, when the ink composition contains a lactam compound, the ink composition tends to have better color development and abrasion resistance, and also has better intermittent ejection characteristics. In addition, the use of a lactam compound tends to effectively suppress the aggregation of the acid dye, and also tends to effectively suppress the increase in ink viscosity when water evaporates.

[0034] Examples of lactam compounds include 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, 3-methoxy-2-pyrrolidone, 3-acetoxy-2-pyrrolidone, 4-pentanelactam, 1-(2-hydroxyethyl)-2-pyrrolidone, and ε-caprolactam.

[0035] In order to obtain an ink composition having better color development and abrasion resistance as well as better intermittent ejection characteristics and initial filling properties, the lactam compound preferably contains one or more selected from the group consisting of N-methyl-2-pyrrolidone, 1-(2-hydroxyethyl)-2-pyrrolidone and ε-caprolactam, more preferably contains one or more selected from the group consisting of 1-(2-hydroxyethyl)-2-pyrrolidone and ε-caprolactam, and even more preferably contains 1-(2-hydroxyethyl)-2-pyrrolidone.

[0036] In order to obtain an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance, the content of the lactam compound is preferably from 1.0 mass % to 15.0 mass % inclusive, more preferably from 2.0 mass % to 10.0 mass % inclusive, and even more preferably from 3.0 mass % to 7.0 mass % inclusive, relative to the total amount of the ink composition.

[0037] 1.5. Other water-soluble organic solvents The ink composition may contain other water-soluble organic solvents in addition to the linear alkyl diol having 2 to 5 carbon atoms and hydroxy groups at both ends and the glycol ether compound having a normal boiling point of 220° C. to 290° C. The other water-soluble organic solvents may be used alone or in combination of two or more.

[0038] Examples of such other water-soluble organic solvents include glycerin; glycols such as diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, ethylene glycol diacetate, propylene glycol monobutyrate, propylene glycol diacetate, and ethylene glycol monobutyl ether acetate; ethylene glycol monomethyl ether (BP: 124°C), ethylene glycol monoethyl ether (BP: 135°C), ethylene glycol monobutyl ether (BP: 171°C), ethylene glycol diethyl ether (BP: 189°C), ethylene glycol mono-n-hexyl ether (BP: 208°C), diethylene glycol ethyl methyl ether (BP: 176°C), diethylene glycol monomethyl ether (BP: 194°C), diethylene glycol monomethyl ether (BP: 194°C), diethylene glycol monomethyl ether (BP: 208 ... glycol ethers such as ethylene glycol monoethyl ether (BP: 203° C.), triethylene glycol dimethyl ether (BP: 215° C.), propylene glycol monomethyl ether (BP: 121° C.), propylene glycol monoethyl ether (BP: 133° C.), propylene glycol monobutyl ether (BP: 170° C.), dipropylene glycol monomethyl ether (BP: 188° C.), dipropylene glycol monoethyl ether (BP: 203° C.), dipropylene glycol monopropyl ether (BP: 210° C.), dipropylene glycol dimethyl ether (BP: 171° C.), and tripropylene glycol dimethyl ether (BP: 215° C.); and alcohols such as methanol, ethanol, n-propyl alcohol, iso-propyl alcohol, n-butanol, 2-butanol, tert-butanol, iso-butanol, n-pentanol, 2-pentanol, 3-pentanol, and tert-pentanol.

[0039] Among them, glycerin and glycols can function as humectants, and glycol ethers can function as penetrating agents.

[0040] In order to obtain an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance, the other water-soluble organic solvent preferably includes one or more selected from the group consisting of glycerin and glycols, and more preferably includes one or more selected from the group consisting of glycerin and triethylene glycol.

[0041] As the other water-soluble organic solvent, it is more preferable to include glycerin. When glycerin is used, an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance is obtained, and an ink composition having better moisturizing effect is likely to be obtained. In addition, when the ink composition includes glycerin, the acid dye is less likely to aggregate in the ink composition, so that an ink composition having better intermittent ejection characteristics and abrasion resistance is likely to be obtained. In addition, the inclusion of glycerin makes it easier to adjust the viscosity of the ink composition, and also tends to be useful for preventing freezing.

[0042] In order to obtain an ink composition having even better color development, intermittent ejection characteristics, and abrasion resistance, the content of the other water-soluble organic solvent is preferably from 0.1% by mass to 15.0% by mass, more preferably from 0.5% by mass to 10.0% by mass, and even more preferably from 1.0% by mass to 5.0% by mass, relative to the total amount of the ink composition.

[0043] 1.6.Surfactants The ink composition may contain a surfactant. The surfactant may be used alone or in combination of two or more kinds.

[0044] The surfactant has a function of lowering the surface tension of the ink composition and adjusting the wettability with a recording medium. Examples of the surfactant include acetylene glycol surfactants, silicone surfactants, and fluorine surfactants.

[0045] Examples of acetylene glycol surfactants include Surfynol (registered trademark) 104, 104E, 104H, 104A, 104BC, 104DPM, 104PA, 104PG-50, 104S, 420, 440, 465, 485, SE, SE-F, 504, 61, DF37, CT111, CT121, CT131, CT136, TG, GA, and DF110D (manufactured by Nissin Chemical Industry Co., Ltd.); Olfine (registered trademark) Examples of suitable terpolymers include (trademark) B, Y, P, A, STG, SPC, E1004, E1010, PD-001, PD-002W, PD-003, PD-004, EXP.4001, EXP.4036, EXP.4051, AF-103, AF-104, AK-02, and SK-14; AE-3 (manufactured by Nissin Chemical Industry Co., Ltd.); and Acetylenol (registered trademark) E00, E00P, E40, and E100 (manufactured by Kawaken Fine Chemical Co., Ltd.).

[0046] Examples of silicone surfactants include polysiloxane compounds such as polyether-modified organosiloxanes. Examples of commercially available polyether-modified organosiloxanes include BYK-306, BYK-307, BYK-333, BYK-341, BYK-345, BYK-346, and BYK-348 (manufactured by BYK Japan Co., Ltd.), KF-351A, KF-352A, KF-353, KF-354L, KF-355A, KF-615A, KF-945, KF-640, KF-642, KF-643, KF-6004, KF-6020, X-22-4515, KF-6011, KF-6012, KF-6015, and KF-6017 (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0047] Examples of fluorine-based surfactants include fluorine-modified polymers, such as BYK-340 (manufactured by BYK Japan Co., Ltd.).

[0048] In order to obtain an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance, the content of the surfactant is preferably from 0.01% by mass to 10.0% by mass, more preferably from 0.05% by mass to 5.0% by mass, and even more preferably from 0.1% by mass to 1.0% by mass, relative to the total amount of the ink composition.

[0049] 1.7. Amines The ink composition may contain amines. The amines may be used alone or in combination of two or more kinds.

[0050] The amines may function as a pH adjuster, and examples of the amines include diethanolamine, triethanolamine, and triisopropanolamine.

[0051] In order to obtain an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance, the content of the amines is preferably from 0.01% by mass to 10% by mass, more preferably from 0.05% by mass to 5.0% by mass, and even more preferably from 0.1% by mass to 1.0% by mass, relative to the total amount of the ink composition.

[0052] 1.8.Other colorants The ink composition may contain other coloring materials such as reactive dyes, direct dyes, pigments, and disperse dyes other than CI Acid Black 172 and CI Acid Black 52:1, as long as the effects of the present invention are achieved. The other coloring materials may be used alone or in combination of two or more.

[0053] In order to obtain an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance, the content of the other coloring materials is preferably 0.1% by mass or more and 20.0% by mass or less, and more preferably 0.5% by mass or more and 10.0% by mass or less, relative to the total amount of the ink composition.

[0054] 1.9.Other Ingredients The ink composition may contain various additives that can be normally used in ink compositions, such as ureas, sugars, preservatives, antifungal agents, dissolution aids, viscosity adjusters, pH adjusters, antioxidants, ultraviolet absorbers, oxygen absorbers, rust inhibitors, corrosion inhibitors, and chelating agents, in addition to the above components. The additives may be used alone or in combination of two or more.

[0055] In order to obtain an ink composition having better color development, intermittent ejection characteristics, and abrasion resistance, the content of the additives is preferably 0.01% by mass or more and 10.0% by mass or less in total relative to the total amount of the ink composition.

[0056] 1.10. Physical properties of ink composition The viscosity of the ink composition at 20°C is preferably from 1.5 mPa·s to 15.0 mPa·s, more preferably from 1.5 mPa·s to 7.0 mPa·s, and even more preferably from 1.5 mPa·s to 5.5 mPa·s.

[0057] From the viewpoint of providing an appropriate wettability and spreadability on a recording medium, the ink composition has an upper limit of surface tension at 25° C. of preferably 40.0 mN / m or less, more preferably 38.0 mN / m or less, even more preferably 35.0 mN / m or less, even more preferably 32.0 mN / m or less, and even more preferably 30.0 mN / m or less. From the same viewpoint, the lower limit of the surface tension is preferably 15.0 mN / m or more, more preferably 20.0 mN / m or more, even more preferably 25.0 mN / m or more, and even more preferably 27.0 mN / m or more. In this specification, the surface tension can be measured as the surface tension when a platinum plate is wetted with the composition at room temperature and normal pressure using a surface tensiometer CBVP-Z (trade name, manufactured by Kyowa Interface Science Co., Ltd.). If the surface tension of the ink composition is within the above range, the intermittent ejection characteristics and initial filling properties in ink jet recording can be improved.

[0058] 1.11. Method for producing ink composition The ink composition can be prepared by mixing an acid dye, a water-soluble organic solvent containing a linear alkyl diol having 2 to 5 carbon atoms and hydroxyl groups at both ends, and a glycol ether compound having a standard boiling point of 220°C to 290°C, water, and optionally a lactam compound, other water-soluble organic solvents, surfactants, amines, other coloring materials, and other components in any order, and removing impurities and foreign matter by filtering or the like as necessary. The method of mixing each component is to add each component sequentially to a container equipped with a stirring device such as a mechanical stirrer and a magnetic stirrer, and stir and mix them. The filtering method can be centrifugation filtering, filter filtering, and the like.

[0059] 2. Inkjet recording method In this embodiment, an inkjet recording method is performed using the ink composition of this embodiment. The inkjet recording method preferably includes a step of ejecting the ink composition from an inkjet head using an inkjet method and depositing it on a recording medium. In other words, the recording method is a recording method in which the ink composition is ejected by an inkjet method and deposited on a recording medium.

[0060] 2.1. Recording medium Examples of the recording medium include absorbent recording media, low absorbent recording media, non-absorbent recording media, and fabrics. Among these, fabrics are preferred.

[0061] In this embodiment, the low absorbency recording medium or the non-absorbent recording medium has a water absorption amount of 10 mL / m2 or less within 30 msec from the start of contact in the Bristow method. 2This refers to a recording medium that is as follows. The Bristow method is the most widely used method for measuring the amount of liquid absorbed in a short period of time, and is also adopted by the Japan Pulp and Paper Technical Association (JAPAN TAPPI). Details of the test method are described in Standard No. 51 "Paper and paperboard - Liquid absorbency test method - Bristow method" of the "JAPAN TAPPI Paper and Pulp Test Method 2000 Edition".

[0062] Non-absorbent recording media or low absorbent recording media can be classified according to the wettability of the recording surface with water. Specifically, the recording media can be characterized by dropping a 0.5 μL water droplet on the recording surface of the recording media and measuring the contact angle drop rate, i.e., the contact angle 0.5 milliseconds after landing and the contact angle 5 seconds after landing. More specifically, as the properties of the recording media, the non-absorbency of a non-absorbent recording media means that the drop rate is less than 1%, and the low absorbency of a low absorbent recording media means that the drop rate is 1% or more and less than 5%. Absorbency means that the drop rate is 5% or more. The contact angle can be measured, for example, using a portable contact angle meter PCA-1 (trade name, Kyowa Interface Science Co., Ltd.).

[0063] Examples of absorbent recording media include those containing fabrics, plain paper such as electrophotographic paper, and inkjet paper, which have high permeability to the ink composition, as well as art paper, coated paper, and cast paper used in general offset printing, which have relatively low permeability to the ink composition.

[0064] An example of a low-absorbency recording medium is coated paper having a coating layer on the surface for receiving oil-based ink. Examples of coated paper include art paper, coated paper, and matte printing paper.

[0065] Examples of non-absorbing recording media include plastic films that do not have an ink absorbing layer, and substrates such as paper coated with plastic, substrates with a plastic film bonded thereto, etc. Examples of plastics include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, and polypropylene.

[0066] In addition to the above-mentioned recording media, metal plates such as iron, silver, copper, and aluminum, and recording media that are non-ink absorbing or have low ink absorbing properties, such as glass, can also be used.

[0067] Examples of raw yarns for fabrics include blended fabrics of silk, cotton, wool, nylon, polyester, polyamide, and polyurethane; natural fibers such as rayon, and synthetic fibers. Fabrics may be made of one type of fiber, or may be made of a blend of two or more types of fibers. Fabrics may be made of the above-listed fibers in any form, such as woven fabric, knitted fabric, and nonwoven fabric.

[0068] When the recording medium is a fabric, the inkjet recording method includes a conveying step of conveying the recording medium including the fabric, and a recording step of recording the ink composition on the recording medium. The recording method of this embodiment may be a textile printing method in which the recording medium includes a fabric. The textile printing method may further include a heating step and a washing step in addition to the recording step. FIG. 1 shows an example of the inkjet recording method of this embodiment. This inkjet recording method includes a treatment liquid composition application step, a heating step, a recording step, and a heating step in this order. The textile printing method when the recording medium is a fabric will be specifically described below.

[0069] 2.2.Printing method The textile printing method may be an inkjet textile printing method in which the ink composition is filled in an inkjet device and used. An example of the inkjet device is a drop-on-demand type inkjet device. The drop-on-demand type inkjet device includes a device that employs an inkjet textile printing method using a piezoelectric element arranged in a head, and a device that employs an inkjet textile printing method using thermal energy from a heater or the like of a heat generating resistor element arranged in a head.

[0070] 2.2.1.Transportation process The conveying step is a step of conveying a recording medium including a fabric. The conveying means for the recording medium may be, for example, a conveying means known in the inkjet method.

[0071] 2.2.2. Recording process The recording process is a process of recording the ink composition on a recording medium. When using an inkjet method, the ink composition is ejected by the inkjet method toward the surface (image forming area) of the fabric, which is at least a part of the recording medium, and adhered to the recording medium to form an image. The ejection conditions may be appropriately determined depending on the physical properties of the ink composition to be ejected.

[0072] 2.2.3.Heating process The textile printing method may further include a heating step of heating the recording medium to which the ink composition is attached after the recording step. By including the heating step, the coloring material can be more satisfactorily dyed into the fibers constituting the fabric. Examples of the heating method include a high-temperature steaming method, a high-pressure steaming method, and a thermosol method.

[0073] In the heating step, the ink composition-attached surface of the recording medium may or may not be pressurized. Examples of heating methods that do not pressurize the ink composition-attached surface of the recording medium include oven drying, i.e., methods that do not involve pressing, such as conveyor ovens and batch ovens. By including such a heating step, the productivity of recorded matter is further improved. Examples of heating methods that pressurize the ink composition-attached surface of the recording medium include heat pressing and wet-on-drying. In this embodiment, pressing refers to applying pressure to the recording medium by contacting a solid.

[0074] The temperature during the heat treatment is preferably 80° C. or higher and 150° C. or lower, and more preferably 90° C. or higher and 110° C. or lower. When the temperature during the heat treatment is within the above range, the colorant tends to be more satisfactorily dyed into the fibers constituting the fabric.

[0075] 2.2.4. Cleaning process The textile printing method may further include a washing step of washing the recording medium to which the ink composition is attached after the heating step. The washing step can effectively remove the acid dye that is not adsorbed on the fiber. The washing step can be performed, for example, using water.

[0076] In this manner, a recorded matter such as a printed matter can be obtained in which an image derived from the ink composition is formed on a recording medium including a fabric.

[0077] 2.2.5. Treatment composition application step The fabric used for printing may be the fabric itself, but it is preferable that the fabric is pretreated with a treatment liquid composition. That is, the printing method preferably includes a step of attaching the treatment liquid composition to the fabric, which is the recording medium. By pretreating the fabric, there is a tendency to obtain a printed product with better abrasion resistance. The pretreatment of the fabric with the treatment liquid composition may be a conventionally known method.

[0078] The treatment liquid composition usually contains a paste, a surfactant, a pH adjuster, a hydrotropic agent, and water, and may also contain silica depending on the application.

[0079] Examples of adhesives include natural gums such as guar gum and locust bean gum; starches; seaweeds such as sodium alginate and funori; plant skins such as pectinic acid; cellulose derivatives such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, and etherified carboxymethyl cellulose; processed starches such as roasted starch, alpha starch, carboxymethyl starch, carboxyethyl starch, and hydroxyethyl starch; processed natural gums such as shiratsum gum and roasted bean gum; alginate derivatives; synthetic glues such as polyvinyl alcohol and polyacrylic esters; and emulsions.

[0080] As the surfactant, reference may be made to the surfactants contained in the ink composition described above. In addition, a nonionic surfactant such as polyoxyethylene diisopropyl ether may also be used.

[0081] Examples of pH adjusters include sodium m-benzenesulfonate, acid ammonium salts, ammonium sulfate, sodium carbonate, and ammonium tartrate.

[0082] Hydrotropic agents include, for example, alkyl ureas such as urea, dimethyl urea, thiourea, monomethyl thiourea, and dimethyl thiourea.

[0083] As for the water, reference may be made to the water contained in the ink composition described above.

[0084] The treatment liquid composition can be prepared by mixing the components in any order and, if necessary, removing impurities and foreign matter by filtration or the like. The components are mixed in a manner that the components are added in sequence to a container equipped with a stirring device such as a mechanical stirrer or a magnetic stirrer, and then stirred and mixed. Filtration methods include centrifugal filtration and filter filtration.

[0085] Examples of methods for applying the treatment liquid composition to a fabric include a dip coating method in which the fabric is immersed in the treatment liquid composition, a roller coating method in which the treatment liquid composition is applied using a mangle roller and a roll coater, etc., a spray coating method in which the treatment liquid composition is sprayed using a spray device, etc., and an inkjet coating method in which the treatment liquid composition is sprayed by an inkjet method. Of these coating methods, the treatment liquid composition may be applied to the fabric by using one method alone, or two or more methods may be combined to apply the treatment liquid composition to the fabric.

[0086] After the treatment liquid composition is applied to the fabric, it is preferable to heat and dry the fabric to which the treatment liquid composition is applied, if necessary. As the drying method, the above-mentioned heating step may be referred to. EXAMPLES

[0087] The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. In the following, "parts" refers to parts by mass unless otherwise specified.

[0088] 1. Preparation of Inkjet Ink Composition (Examples 1 to 16 and Comparative Examples 1 to 5) Each component was placed in a mixing tank so as to obtain the composition shown in Table 1 or 2, and mixed and stirred for 2 hours using a magnetic stirrer. The mixture was then filtered through a membrane filter having a pore size of 5 μm, thereby obtaining inkjet ink compositions according to the examples and comparative examples. In Tables 1 and 2, the mass ratio (alkyl diol / glycol ether compound) indicates the mass ratio of alkyl diol to glycol ether compound. The numerical values ​​in Tables 1 and 2 indicate mass %. Ion-exchanged water was used as the water, and was added so that the mass of each ink was 100 mass %.

[0089] The components shown in Tables 1 and 2 are as follows. [Acid dye] ABk172…CIAcid Black 172 (commercial product) ABk52:1…CIAcid Black 52:1 (commercial product) ABk1…CIAcid Black 1 (commercially available)

[0090] [Water-soluble organic solvent] (Straight-chain alkyl diol having 2 to 5 carbon atoms and hydroxyl groups at both ends) Ethylene glycol 1,3-Propanediol 1,4-Butanediol 1,5-Pentanediol

[0091] (Other alkyl diols) 3-Methyl-1,5-pentanediol Triethylene glycol

[0092] (Glycol ether compounds) Triethylene glycol monobutyl ether (BP: 278°C) Diethylene glycol monobutyl ether (BP: 231℃)

[0093] [Other glycol ether compounds] Diethylene glycol monomethyl ether (BP: 194℃)

[0094] [Lactam Compounds] 1-(2-hydroxyethyl)-2-pyrrolidone ε-Caprolactam

[0095] [Other lactam compounds] N-Methyl-2-pyrrolidone

[0096] [Other water-soluble organic solvents (humectants)] Glycerin

[0097] [Surfactant] PD-002W: Olfin (registered trademark) PD-002W (product name, Nissin Chemical Industry Co., Ltd.)

[0098] [Amines (pH adjusters)] Triethanolamine

[0099] 2. Preparation of Processing Liquid Composition 5.0 parts by mass of polyoxyethylene diisopropyl ether (oxyethylene amount in the structure is 30 moles), 5.0 parts by mass of etherified carboxymethyl cellulose, 100.0 parts by mass of urea, and 10.0 parts by mass of sodium m-benzenesulfonate were thoroughly mixed. Then, 1000.0 parts by mass of ion-exchanged water was added little by little while stirring for 30 minutes under the condition of 60°C, and then 30.0 parts by mass of sodium carbonate was further added to the stirred solution and stirred for 10 minutes. Then, the obtained solution was filtered through a membrane filter with a pore size of 10 μm to obtain a treatment liquid composition.

[0100] 3. Preparation of printed items 3.1. Preparation of fabric having treatment liquid composition applied thereto The treatment liquid composition obtained above was applied to a fabric (100% silk, basis weight 90 g / m 2 ) and then squeezed with a mangle at a pickup rate of 20% and dried to obtain a fabric having the treatment liquid composition adhered thereto.

[0101] 3.2.Textile printing Each of the inkjet ink compositions in Examples 1 to 16 and Comparative Examples 1 to 5 was filled into the cartridge of an inkjet printer EP-805A (product name, Seiko Epson Corporation). Then, each ink composition was applied to the fabric to which the treatment liquid composition obtained above had been applied in a solid pattern with an ink discharge amount of 100% duty at a resolution of 1440 x 720 dpi, to record an image. Note that the "solid pattern" refers to a pattern in which dots are recorded in all pixels, which is the minimum recording unit area defined by the recording resolution. Each of the fabrics on which the images were recorded was steamed at 100°C for 20 minutes, then washed at 55°C for 10 minutes using an aqueous solution containing 0.2% by mass of Laccol STA (surfactant, manufactured by Meisei Chemical Industry Co., Ltd.), and dried to obtain each printed item.

[0102] 4. Evaluation of printed items 4.1.Color development The color development of each of the obtained printed textiles was evaluated. Specifically, the OD value of the image of each of the obtained printed textiles was measured using a colorimeter (Gretag Macbeth Spectrolino (trade name), manufactured by X-Rite). Based on the obtained OD value, the color development was evaluated according to the following evaluation criteria. The results are shown in Tables 3 and 4. (Evaluation Criteria) A:OD value is 1.45 or more B: OD value is 1.40 or more and less than 1.45 C:OD value is less than 1.40

[0103] 4.2.Intermittent ejection characteristics Each of the inkjet ink compositions in Examples 1 to 16 and Comparative Examples 1 to 5 was filled into the cartridge of an inkjet printer EP-805A (product name, Seiko Epson Corporation). Then, in a thermostatic room at 35°C and 20% RH, the ink compositions were ejected from all nozzles, and a confirmation pattern of the landing position was recorded. From the confirmation pattern, it was confirmed that all ink compositions were ejected normally. Next, a 5-minute idle run was performed, which is a scan in which ink is not ejected. During this time, no flushing was performed, and during the idle run, a slight vibration was performed, which is a vibration that does not eject ink. After that, the ink composition was ejected from all the nozzles, and a recording pattern of the landing positions was recorded. The presence or absence of ejection from the nozzles and the presence or absence of landing position deviation (distortion) were confirmed, and the intermittent ejection characteristics were evaluated according to the following evaluation criteria. The results are shown in Tables 3 and 4. (Evaluation Criteria) A: There were no nozzles that did not eject, and there was no deviation in the landing position. A-: There were no nozzles that did not eject ink, but there were one to two nozzles in which the landing position was shifted. B: There were no nozzles that did not eject ink, but there were 3 to 9 nozzles in which the landing position was shifted. B-: There were no nozzles that did not eject ink, but there were 10 or more nozzles where the landing position was shifted. C: There were nozzles that did not eject ink, and there were also nozzles where the landing position was shifted.

[0104] 4.3.Abrasion resistance The obtained printed materials were evaluated for their abrasion resistance. Specifically, the obtained printed materials were subjected to a color fastness test against abrasion using a type I (crock meter) tester in accordance with the dry test of ISO-105 X12, i.e., a test using dry white cotton for abrasion. The abrasion resistance was evaluated according to the following evaluation criteria using a staining gray scale. The results are shown in Tables 3 and 4. (Evaluation Criteria) A: Level 4 or higher B: Grade 3 or above but below grade 4 C: Less than 3rd grade

[0105] 4.4.Initial filling property Each of the inkjet ink compositions in Examples 1 to 16 and Comparative Examples 1 to 5 was filled into the cartridge of an inkjet printer EP-805A (product name, Seiko Epson Corporation). Then, in a thermostatic room at 35° C. and 20% RH, an initial filling operation was performed on the head according to the initial filling sequence defined by the inkjet printer. A nozzle check was performed to confirm whether the inkjet ink composition could be ejected from all the nozzles of the head. If there was a nozzle that could not eject the inkjet ink composition, the head was cleaned, that is, the ink in the nozzle was sucked, and a nozzle check was performed again. The number of cleanings required until the inkjet ink composition could be ejected from all the nozzles was counted, and the initial filling property was evaluated according to the following evaluation criteria. The results are shown in Tables 3 and 4. (Evaluation Criteria) A: With only the initial filling sequence, ejection occurred from all nozzles without performing cleaning. B: It took one cleaning cycle before ink could be ejected from all nozzles. C: Two or more cleaning cycles were required before ink could be ejected from all nozzles.

[0106] As shown in Tables 3 and 4, it was found that the ink composition of this embodiment has excellent color development, intermittent ejection characteristics, and abrasion resistance.

[0107] Furthermore, by comparing Examples 1 and 2 with Example 3, it was found that when the content of the acid dye is 11 mass% or more relative to the total amount of the ink composition, an ink composition having better intermittent ejection characteristics and abrasion-resistant coloring properties as well as even better coloring properties can be obtained.

[0108] A comparison between Examples 1 and 5 and Examples 4 and 6 shows that by using 1,3-propanediol or 1,4-butanediol as the specific linear alkyl diol, it is possible to obtain excellent intermittent ejection characteristics as well as excellent color development and abrasion resistance. A comparison between Examples 1 and 5 shows that by using 1,3-propanediol as the specific linear alkyl diol, it is possible to obtain even more excellent intermittent ejection characteristics as well as excellent color development and abrasion resistance.

[0109] Comparing Examples 1 and 10 with Examples 11 and 12, it was found that when the content of the specific alkyl diol is 7.0 mass% or more and 13.0 mass% or less relative to the total amount of the ink composition, an ink composition having excellent color development, as well as better friction resistance and intermittent ejection characteristics can be obtained.

[0110] Comparing Examples 1 and 13 with Examples 14 and 15, it was found that when the content of the specific glycol ether compound is 2.0 mass % or more and 5.0 mass % or less with respect to the total amount of the ink composition, an ink composition having excellent color development, as well as better abrasion resistance and intermittent ejection characteristics can be obtained.

[0111] Comparing Examples 1, 10, and 13 with Examples 11, 12, 14, and 15, it was found that when the mass ratio of the specific alkyl diol to the specific glycol ether compound (specific alkyl diol / specific glycol ether compound) was 2.3 or more and 6.0 or less, an ink composition having excellent color development, as well as better abrasion resistance and intermittent ejection characteristics could be obtained.

[0112] Comparing Examples 1, 8, and 9 with Example 16, it was found that when the ink composition contains a lactam compound, an ink composition having superior color development and abrasion resistance as well as superior intermittent ejection characteristics can be obtained.

[0113] Comparing Examples 1 and 8 with Example 9, it was found that when the ink composition contains one or more lactam compounds selected from the group consisting of 1-(2-hydroxyethyl)-2-pyrrolidone and ε-caprolactam, an ink composition having superior color development and abrasion resistance as well as further superior intermittent ejection characteristics and initial filling properties can be obtained.

Claims

1. An ink composition comprising an acid dye, a water-soluble organic solvent, and water, The acid dye includes at least one selected from the group consisting of C.I. Acid Black 172 and C.I. Acid Black 52:1; the content of the acid dye is 10.0% by mass or more relative to the total amount of the ink composition; The water-soluble organic solvent contains a linear alkyl diol having 2 to 5 carbon atoms and hydroxyl groups at both ends, and a glycol ether compound having a normal boiling point of 220° C. to 290° C. Textile inkjet ink composition.

2. The textile ink-jet ink composition of claim 1 further comprising a lactam compound.

3. 3. The ink-jet printing ink composition according to claim 2, wherein the lactam compound comprises at least one compound selected from the group consisting of 1-(2-hydroxyethyl)-2-pyrrolidone and ε-caprolactam.

4. 3. The ink-jet printing ink composition according to claim 1, wherein the linear alkyl diol comprises at least one member selected from the group consisting of ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,5-pentanediol.

5. The inkjet ink composition for textile printing according to claim 1 or 2, wherein the glycol ether compound comprises at least one compound selected from the group consisting of diethylene glycol monobutyl ether and triethylene glycol monobutyl ether.

6. The inkjet textile printing ink composition according to claim 1 or 2, wherein a content of the linear alkyl diol is from 1.0% by mass to 20.0% by mass with respect to a total amount of the ink composition.

7. The inkjet textile printing ink composition according to claim 1 or 2, wherein the content of the glycol ether compound is from 0.5% by mass to 15.0% by mass with respect to the total amount of the ink composition.

8. The inkjet printing ink composition according to claim 1 , wherein a mass ratio of the linear alkyl diol to the glycol ether compound is from 1.0 to 12.

0.

9. The inkjet textile printing ink composition according to claim 2 or 3, wherein the content of the lactam compound is 1.0% by mass or more and 15.0% by mass or less with respect to the total amount of the ink composition.

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