JP7256954B2 - DISPERSION, INK COMPOSITION FOR INKJET RECORDING, AND INKJET RECORDING METHOD - Google Patents

Description

The present invention relates to a dispersion liquid, an ink composition for inkjet recording, and an inkjet recording method.

The ink jet recording method is a recording method in which droplets of an ink composition are ejected from a nozzle and attached to a recording medium such as paper for printing. This inkjet recording method is characterized by being able to print high-resolution and high-quality images at high speed, and has come to be used in various technical fields. In recent years, there has been an increasing demand for textile printing on cloth and printing on films such as polypropylene.

For example, US Pat. No. 6,300,000 discloses reacting cyanuric chloride with about 3 equivalents of a second compound or mixture of second compounds to displace all reactive chlorines to form a substituted triazine; and said substituted triazine. A method of modifying a pigment is described comprising reacting with a surface of the pigment to form a surface-modified pigment.

JP 2015-145497 A

In the ink jet recording method on a recording medium such as fabric or film, in order to ensure the fastness of the fixed image, a fixing resin such as polyurethane is mixed in the ink composition, and the fixing resin is melted by heat or formed into a film. A technique is used in which coloring materials are dispersed in the surface to give strength.
On the other hand, apart from the fixing resin, a colorant dispersant is used to disperse the colorant. The colorant dispersant tends to interfere with image fixation by entering between the fixing resin and the colorant. On the other hand, if a large amount of fixing resin is used, the viscosity of the ink composition tends to increase, which tends to cause clogging of the recording head.
In addition, when a resin emulsion is used as the fixing resin, the resin particles do not remain in the fibers of the fabric, so that a large amount of the resin particles must be used, and sedimentation tends to occur in the ink composition. Furthermore, as a method for improving the adhesion to various recording media, a method of applying an anchoring agent that brings the recording medium and the image into close contact is adopted. However, this causes an increase in the material cost of the recording medium and an increase in the size of devices such as a coating device.

In the ink composition of Patent Document 1, the self-dispersing pigment obtained by reacting a substituted triazine substituted with cyanuric chloride and a pigment reacts with the hydroxyl groups of cellulose and the hydroxyl groups on the film surface because the cyanuric chloride is fully substituted. There are no parts, and the friction fastness does not increase.

The present inventors have found that a dispersion exhibiting excellent viscosity can be obtained by using a resin synthesized from a modified polyvinyl alcohol into which an anionic group or a cationic group has been introduced and a triazine compound having two or more halogen atoms. Furthermore, it has been found that an ink composition can be obtained which is excellent in fastness to rubbing of an image fixed to a fabric and excellent in abrasion resistance of an image fixed to a film.

That is, the dispersion according to the present invention comprises a resin synthesized from a modified polyvinyl alcohol into which an anionic group or a cationic group is introduced and a triazine compound having two or more halogen atoms, a water-insoluble colorant, water, contains
The resin preferably has residual halogen atoms derived from the triazine compound, and is preferably synthesized by reacting the modified polyvinyl alcohol and the triazine compound at a temperature of 50°C or higher and lower than 70°C.
The triazine compound is preferably a triazine compound having 3 halogen atoms.
The dispersion preferably further contains a polyurethane resin containing an active hydrogen group.

The ink composition for inkjet recording according to the present invention preferably contains the dispersion.
The ink jet recording method according to the present invention includes an ink application step of ejecting the ink composition from a recording head and attaching it to a recording medium.
The recording medium preferably has hydroxy groups on its surface.
The inkjet recording method preferably includes, simultaneously with or after the ink application step, a heating step of heating the recording medium to a temperature higher than the reaction temperature between the hydroxyl group and the halogen atom in the resin.
The heating temperature in the heating step is preferably 60° C. or higher.

Hereinafter, an embodiment of the present invention (hereinafter referred to as "this embodiment") will be described in detail, but the present invention is not limited to this, and various modifications are possible without departing from the gist thereof. is.

Dispersion The dispersion of the present embodiment comprises a modified polyvinyl alcohol into which an anionic group or a cationic group has been introduced (hereinafter also simply referred to as "modified polyvinyl alcohol") and a triazine compound having two or more halogen atoms (hereinafter simply referred to as " triazine compound”), a resin synthesized by (hereinafter also simply referred to as “resin (A)”), a water-insoluble coloring material, and water.
According to the above-described dispersion liquid, an ink composition having excellent viscosity and excellent rubbing fastness of fixed images on fabric and excellent rubbing and abrasion resistance of fixed images on film can be obtained.

Resin (A)
Resin (A) preferably has residual halogen atoms derived from the triazine compound. Having residual halogen atoms further reacts with hydroxyl groups on the surface of the recording medium after printing, and an ink composition having excellent rubbing fastness and abrasion resistance can be obtained.

Since the modified polyvinyl alcohol has an anionic group or a cationic group, the water-insoluble colorant can be highly dispersed in water, and the viscosity of the dispersion or ink composition can be lowered.
The “anionic group” means a group that is liberated in the ink composition and introduces an anion into the molecular chain of the modified polyvinyl alcohol.
The “cationic group” means a group that is liberated in the ink composition and introduces an anion into the molecular chain of the modified polyvinyl alcohol.
Examples of anionic groups include, but are not limited to, sulfo groups, carboxyl groups, and salts thereof.
Examples of cationic groups include, but are not particularly limited to, quaternary ammonium groups, amino groups, and salts thereof.

The degree of saponification of the modified polyvinyl alcohol is preferably 30 mol% or more and 100 mol% or less, more preferably 50 mol% or more and 100 mol% or less, and still more preferably 70 mol% or more and 100 mol% or less. By having such a degree of saponification, the ink composition reacts with the triazine compound described below and has excellent rubbing fastness and abrasion resistance.
The “degree of saponification” means the proportion (mol %) of monomer units to which a hydroxy group has been introduced, among the monomer units contained in the modified polyvinyl alcohol.

The viscosity of the modified polyvinyl alcohol is preferably 0.5 mPa·s or more and 100 mPa·s or less, more preferably 1.0 mPa·s or more and 50 mPa·s or less, and still more preferably 1.5 mPa·s or more and 10 mPa·s. It is below. By using a modified polyvinyl alcohol having a degree of polymerization exhibiting such a viscosity, it is possible to obtain a dispersion exhibiting low viscosity while exhibiting excellent rubbing fastness and abrasion resistance.
The viscosity is the viscosity measured at 20° C. in a 4 mass % aqueous solution of modified polyvinyl alcohol.

Examples of modified polyvinyl alcohol include sulfonic acid-modified polyvinyl alcohol (commercially available products include Gohsenex (registered trademark) series L-3266 and CKS-50 (product names, manufactured by The Nippon Synthetic Chemical Industry Co., Ltd.)), Quaternary ammonium-modified polyvinyl alcohol (commercially available products include, for example, Gohsenex (registered trademark) series K-434 (product name, manufactured by The Nippon Synthetic Chemical Industry Co., Ltd.)).
Among these, modified polyvinyl alcohol into which an anion group is introduced is preferred, and sulfonic acid-modified polyvinyl alcohol is more preferred.

A triazine compound has two or more halogen atoms. Having two or more halogen atoms, the triazine compound can further react with other hydroxy groups after reacting with the modified polyvinyl alcohol, and exhibits excellent rub fastness and scratch resistance.
The triazine compound preferably has 2 or 3 halogen atoms, and more preferably 3 halogen atoms from the viewpoint of obtaining better viscosity and abrasion resistance.

Examples of triazine compounds include, but are not limited to, 2,4,6-trichloro-1,3,5-triazine (also known as cyanuric chloride), 2,4-dichloro-1,3,5-triazine, 2- (4-biphenylyl)-4,6-dichloro-1,3,5-triazine, 2-(3-carboxanilino)-4,6-dichloro-1,3,5-triazine, 2,4-dichloro- 6-phenyl-1,3,5-triazine, 2,4-dichloro-6-morpholino-1,3,5-triazine. These may be used singly or in combination of two or more.
Among these, 2,4,6-trichloro-1,3,5-triazine and 2,4-dichloro-1,3,5-triazine are preferred. ,4,6-trichloro-1,3,5-triazine is preferred.

In the resin (A), the equivalent ratio of the halogen atom of the triazine compound to the hydroxyl group of the modified polyvinyl alcohol is preferably 120/100 to 300/100, more preferably 130/100 to 130/100, as halogen atom/hydroxy group. 250/100, more preferably 140/100 to 220/100.

In the resin (A), the number of halogen atoms in one molecule of the triazine compound was a, the molar amount of the triazine compound was x (mol), and the molar amount of the hydroxyl group (OH group) of the modified polyvinyl alcohol was y (mol). In this case, the following formula (1a) is preferably satisfied, the following formula (1b) is more preferably satisfied, and the following formula (1c) is further preferably satisfied.
0.5≦(x×ay)/x≦2.0 (1a)
0.7≦(x×ay)/x≦1.8 (1b)
0.8≦(x×ay)/x≦1.6 (1c)
By satisfying the above formula, halogen atoms tend to remain in the resin (A), and the rubbing fastness and abrasion resistance after printing can be improved.

Resin (A) is synthesized from modified polyvinyl alcohol and a triazine compound.
The resin (A) is not particularly limited, but is preferably synthesized by reacting a modified polyvinyl alcohol and a triazine compound at a temperature of 50°C or more and less than 70°C.
For the reaction, for example, the modified polyvinyl alcohol and the triazine compound may be mixed and suspended in an aqueous medium for reaction.
The reaction temperature is preferably 50°C or higher and lower than 70°C, more preferably 55°C or higher and 65°C or lower.
The equivalent ratio (X group/OH group) in the reaction is preferably within the range described above. Moreover, in the reaction, it is more preferable to satisfy the above formula (1a), formula (1b), or formula (1c).

In the dispersion liquid of the present embodiment, the content of the resin (A) is preferably 0.5% by mass or more and 40% by mass or less, more preferably 1.0% by mass, relative to the total amount (100% by mass) of the dispersion liquid. % by mass or more and 30% by mass or less, more preferably 2.0% by mass or more and 20% by mass or less.
In the dispersion liquid of the present embodiment, the mass ratio of the water-insoluble colorant and the resin (A) is preferably 40/60 to 90/10, more preferably 40/60 to 90/10, as water-insoluble colorant/resin (A). is 50/50 to 80/20, more preferably 55/45 to 75/25.

Water-Insoluble Colorant The water-insoluble colorant used in the present embodiment is not particularly limited, but includes pigments and oil-soluble dyes.
Although the oil-soluble dye is not particularly limited, for example, disperse dyes, vat dyes, or organic solvent-soluble dyes can be used.

Although the pigment of the present embodiment is not particularly limited, more specific examples include the following.

Examples of carbon black used in black ink include, but are not limited to, No. 2300, No. 900, MCF88, no. 33, No. 40, No. 45, No. 52, MA7, MA8, MA100, No. 2200B, etc. (manufactured by Mitsubishi Chemical Corporation), Raven 5750, Raven 5250, Raven 5000, Raven 3500, Raven 1255, Raven 700, etc. (manufactured by Carbon ColumbiaR1), 400Rega , Regal 330R, Regal 660R, Mogul L, Monarch 700, Monarch 800, Monarch 880, Monarch 900, Monarch 1000, Monarch 1100, Monarch 1300, Monarch 1400, etc. (manufactured by CABOT JAPAN, K.K.K.) ＦＷ１、Ｃｏｌｏｒ Ｂｌａｃｋ ＦＷ２、Ｃｏｌｏｒ Ｂｌａｃｋ ＦＷ２Ｖ、Ｃｏｌｏｒ Ｂｌａｃｋ ＦＷ１８、Ｃｏｌｏｒ Ｂｌａｃｋ ＦＷ２００、Ｃｏｌｏｒ Ｂ１ａｃｋ Ｓ１５０、Ｃｏｌｏｒ Ｂｌａｃｋ Ｓ１６０、Ｃｏｌｏｒ Ｂｌａｃｋ Ｓ１７０、Ｐｒｉｎｔｅｘ ３５、Ｐｒｉｎｔｅｘ Ｕ、Ｐｒｉｎｔｅｘ Ｖ、Ｐｒｉｎｔｅｘ １４０Ｕ、Ｓｐｅｃｉａｌ Ｂｌａｃｋ ６、Ｓｐｅｃｉａｌ Ｂｌａｃｋ ５、 Special Black 4A, Special Black 4 (manufactured by Degussa).

Pigments used in the white ink are not particularly limited, but examples include C.I. I. Pigment White 6, 18, 21, titanium oxide, zinc oxide, zinc sulfide, antimony oxide, zirconium oxide, white hollow resin particles and polymer particles.

Pigments used in the yellow ink are not particularly limited, but examples include C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 16, 17, 24, 34, 35, 37, 53, 55, 65, 73, 74, 75, 81, 83, 93, 94, 95, 97, 98, 99, 108, 109, 110, 113, 114, 117, 120, 124, 128, 129, 133, 138, 139, 147, 151, 153, 154, 167, 172, 180.

Pigments used in magenta ink are not particularly limited, but examples include C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 40, 41, 42, 48:2, 48:5, 57:1, 88, 112, 114, 122, 123, 144, 146, 149, 150, 166, 168, 170, 171, 175, 176, 177, 178, 179, 184, 185, 187, 202, 209, 219, 224, 245, and C.I. I. Pigment Violet 19, 23, 32, 33, 36, 38, 43, 50.

Pigments used in cyan ink are not particularly limited, but examples include C.I. I. Pigment Blue 1, 2, 3, 15, 15:1, 15:2, 15:3, 15:34, 15:4, 16, 18, 22, 25, 60, 65, 66, and C.I. I. bat blue 4,60.

Pigments other than those described above are not particularly limited, but include, for example, C.I. I. Pigment Green 7, 10, C.I. I. Pigment Brown 3, 5, 25, 26, and C.I. I. Pigment Orange 1, 2, 5, 7, 13, 14, 15, 16, 24, 34, 36, 38, 40, 43, 63.

The average particle size of the pigment is preferably 50 nm or more and 300 nm or less, more preferably 55 nm or more and 200 nm or less, and still more preferably 60 nm or more and 150 nm or less, from the viewpoint of more effectively and reliably exhibiting the effects of the present invention. , and more preferably 65 nm or more and 100 nm. Note that the average particle size in this specification is based on volume unless otherwise specified. As a measuring method, for example, it can be measured by a particle size distribution measuring apparatus using a laser diffraction scattering method as a measuring principle. Examples of the particle size distribution analyzer include a particle size distribution meter (for example, Microtrac UPA manufactured by Nikkiso Co., Ltd.) based on the dynamic light scattering method.

In the dispersion liquid of the present embodiment, the content of the water-insoluble colorant is preferably 1.0% by mass or more and 25% by mass or less, more preferably 2.0% by mass, with respect to 100% by mass of the total amount of the dispersion liquid. % or more and 20 mass % or less, more preferably 3.0 mass % or more and 15 mass % or less.

Water The ink composition of the present embodiment contains water. Examples of water include, but are not limited to, pure water such as ion-exchanged water, ultrafiltrated water, reverse osmosis water, and distilled water, and ultrapure water.
In the dispersion of the present embodiment, the water content is preferably 60% by mass or more and 99% by mass or less, more preferably 70% by mass or more and 95% by mass or less, relative to 100% by mass of the total amount of the dispersion. , more preferably 75% by mass or more and 90% by mass or less.

Polyurethane-Based Resin The dispersion of the present embodiment further contains a polyurethane-based resin containing an active hydrogen group (hereinafter also simply referred to as "polyurethane-based resin") from the viewpoint of further improving rubbing fastness and abrasion resistance. The active hydrogen groups contained in the polyurethane resin react with the halogen atoms contained in the resin (A) to form a crosslinked structure, which is thought to further improve the rubbing fastness and abrasion resistance. No limitation The active hydrogen group includes, but is not limited to, a hydroxy group and an amino group. Among these, a hydroxy group is preferred.
Examples of polyurethane-based resins include polyether-type urethane resins containing ether bonds in the main chain, polyester-type urethane resins containing ester bonds in the main chain, and polycarbonate-type urethane resins containing carbonate bonds in the main chain, in addition to urethane bonds. . These urethane resins are used singly or in combination of two or more.

The polyurethane resin is preferably added as resin particles. Resin particles (hereinafter also referred to as "resin dispersion" and "resin emulsion") are particles containing a resin. The resin particles of the present embodiment may be self-dispersing resin particles (self-dispersing resin particles) into which a hydrophilic component necessary for stably dispersing in water is introduced, or they may be dispersed in water by using an external emulsifier. It may be a dispersible resin particle.
The average particle diameter of the resin particles is preferably 50 nm or more and 300 nm or less, more preferably 55 nm or more and 200 nm or less, and still more preferably 60 nm or more and 150 nm or less, from the viewpoint of more effectively and reliably exhibiting the effects of the present invention. and more preferably 65 nm or more and 100 nm or less. The average particle size of the resin particles can be measured, for example, by the measurement method exemplified as the method for measuring the average particle size of the pigment.

Commercially available polyurethane resins include UW-1501F, UW-5002 (product names, manufactured by Ube Industries, Ltd.), Takelac (registered trademark) series W-6061, W-6110, WS-6021 (product names , manufactured by Mitsui Chemicals, Inc.), U-coat (registered trademark) series UX-485, UX-150, UX-390, and UX-200 (product names, manufactured by Sanyo Chemical Industries, Ltd.).

When the dispersion of the present embodiment contains a polyurethane-based resin, the content of the polyurethane-based resin is preferably based on 100% by mass of the total amount of the dispersion, from the viewpoint of more effectively and reliably exhibiting the effects of the present invention. is 1.0% by mass or more and 20% by mass or less, more preferably 2.0% by mass or more and 15% by mass or less, and still more preferably 3.0% by mass or more and 10% by mass or less.
When the dispersion of the present embodiment contains a polyurethane-based resin, the mass ratio of the resin (A) to the polyurethane-based resin (resin (A)/polyurethane-based resin) is such that the effects of the present invention are more effectively and reliably achieved. From the viewpoint of performance, it is preferably 30/70 to 80/20, more preferably 40/60 to 70/30, and still more preferably 45/65 to 65/35.

The dispersion of this embodiment may contain a deacidifying agent for the purpose of neutralizing the acid present or produced in the dispersion. Examples of the deacidifier include, but are not particularly limited to, amine compounds such as triethylamine and triethanolamine, sodium hydroxide, and potassium hydroxide.
In the dispersion of the present embodiment, the content of the deoxidizing agent is preferably 0.5% by mass or more and 10% by mass or less, more preferably 1.0% by mass or more, relative to 100% by mass of the total amount of the dispersion. It is 8.0 mass % or less, more preferably 2.0 mass % or more and 5.0 mass % or less.

Ink Composition The ink composition for inkjet recording of the present embodiment (hereinafter also simply referred to as "ink composition") contains the dispersion liquid of the present embodiment described above.
In the ink composition of the present embodiment, the content of the resin (A) is preferably 0.1% by mass or more and 30% by mass or less, more preferably 0.5% by mass, relative to 100% by mass of the total amount of the ink composition. % by mass or more and 20% by mass or less, more preferably 1.0% by mass or more and 10% by mass or less.
In the ink composition of the present embodiment, the content of the water-insoluble colorant is preferably 0.5% by mass or more and 20% by mass or less, more preferably 1.0% by mass or more, based on 100% by mass of the total amount of the ink composition. It is 0% by mass or more and 15% by mass or less, more preferably 2.0% by mass or more and 10% by mass or less.
The mass ratio of the water-insoluble colorant to the resin (A) is preferably within the above-mentioned dispersion liquid range.
When the ink composition of the present embodiment contains a polyurethane-based resin, the content of the polyurethane-based resin is preferably 0.5% by mass or more and 20% by mass or less with respect to 100% by mass of the total amount of the ink composition. , more preferably 0.8% by mass or more and 10% by mass or less, and still more preferably 1.0% by mass or more and 5.0% by mass or less.

Water-Soluble Organic Solvent The ink composition of the present embodiment may further contain a water-soluble organic solvent from the viewpoint of viscosity adjustment and moisturizing effect.

Examples of water-soluble organic solvents include, but are not limited to, lower alcohols (e.g., methanol, ethanol, 1-propanol, isopropanol, 1-butanol, 2-butanol, isobutanol, 2-methyl-2-propanol, and 1,2-hexanediol), glycols (eg, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, propylene glycol, dipropylene glycol, and tripropylene glycol), glycerin, acetins (eg, monoacetin, diacetin, and triacetin), derivatives of glycols (e.g., triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monopropyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol monoethyl ether, tetraethylene glycol dimethyl ether, and tetraethylene glycol diethyl ether), 1-methyl-2-pyrrolidone, β-thiodiglycol, and sulfolane. These water-soluble organic solvents may be used singly or in combination of two or more.

The content of the water-soluble organic solvent is preferably 1.0% by mass or more and 50% by mass or less, more preferably 5.0% by mass or more and 40% by mass or less with respect to 100% by mass of the total amount of the ink composition. , more preferably 10% by mass or more and 30% by mass or less.

Surfactant The ink composition of the present embodiment preferably further contains a surfactant from the viewpoint that the ink composition can be stably ejected by an inkjet recording method and the permeation of the ink composition can be appropriately controlled. contains. The surfactant is not particularly limited, but examples thereof include acetylene glycol surfactants (eg, 2,4,7,9-tetramethyl-5-decyne-4,7-diol and 2,4,7,9 - Alkylene oxide adducts of tetramethyl-5-decyne-4,7-diol and alkylene oxides of 2,4-dimethyl-5-decyne-4-ol and 2,4-dimethyl-5-decyne-4-ol adducts), fluorosurfactants (e.g., perfluoroalkyl sulfonates, perfluoroalkyl carboxylates, perfluoroalkyl phosphate esters, perfluoroalkyl ethylene oxide adducts, perfluoroalkyl betaine, and perfluoroalkyl fluoroalkylamine oxide compounds), and silicone-based surfactants (eg, polysiloxane-based compounds and polyether-modified organosiloxanes).

The content of the surfactant is preferably 0.1% by mass or more and 5.0% by mass or less with respect to 100% by mass of the total amount of the ink composition, from the viewpoint of more effectively and reliably exhibiting the effects of the present invention. , more preferably 0.2% by mass or more and 3.0% by mass or less, and still more preferably 0.2% by mass or more and 1.0% by mass or less.

Other additives in the ink composition of the present embodiment include softeners, waxes, dissolution aids, viscosity modifiers, antioxidants, anti-mold/preservatives, anti-mold agents, anti-corrosion agents, and additives that affect dispersion. Various additives such as a chelating agent (eg, sodium ethylenediaminetetraacetate) for trapping metal ions to be provided may be included as appropriate.

Physical Properties of Ink Composition The viscosity of the ink composition of the present embodiment is preferably less than 0.03 Pa·s, more preferably less than 0.01 Pa·s at a shear rate of 10 (1/s) at 25° C. and more preferably less than 0.005 Pa·s. Although the viscosity of the dispersion is not particularly limited, it is, for example, 0.00001 Pa·s or more at 25° C. and a shear rate of 10 (1/s).
The viscosity of the ink composition of the present embodiment is preferably less than 0.03 Pa s, more preferably less than 0.01 Pa s, and still more preferably less than 0.01 Pa s at a shear rate of 1000 (1/s) at 25°C. It is less than 0.005 Pa·s. Although the viscosity of the dispersion is not particularly limited, it is, for example, 0.00001 Pa·s or more at 25° C. and a shear rate of 1000 (1/s).
The above viscosity is a value measured at 25° C. with an E-type viscometer (eg, TVE-22 manufactured by Toki Sangyo Co., Ltd.).

Ink Jet Recording Method The ink jet recording method of the present embodiment includes an ink applying step of ejecting the ink composition of the present embodiment from a recording head to adhere it to a recording medium.

The above-described inkjet recording method is a recording method in which the ink composition is loaded into an inkjet device and used. Although the inkjet device is not particularly limited, for example, a drop-on-demand inkjet device can be used. This drop-on-demand type inkjet device includes a device that employs an inkjet textile printing method using piezoelectric elements provided in the head, and an inkjet device that uses thermal energy from a heater of a heat-generating resistance element provided in the head. There are devices that employ recording methods, and any inkjet recording method may be used. Each step of the inkjet recording method will be described in detail below.

Ink application step In the ink application step of the present embodiment, for example, an ink composition is ejected by an inkjet method toward the surface of a recording medium (image forming area) and adhered to the recording medium to form an image. . Note that the ejection conditions may be appropriately determined depending on the physical properties of the ink composition to be ejected.

Recording Medium The recording medium preferably has a hydroxy group on its surface from the viewpoint of improving rubbing fastness and abrasion resistance. The hydroxy group of the recording medium reacts with the residual halogen atoms of the resin (A) contained in the ink composition, which strengthens the fixation to the recording medium and improves the rubbing fastness and abrasion resistance. It is considered to be a thing. However, it is not limited to this factor.

Examples of the recording medium include, but are not limited to, cloth, paper, plastic, and a recording medium obtained by coating a paper substrate with plastics.
The fabric is not particularly limited, but examples thereof include natural fibers and synthetic fibers such as silk, cotton, wool, nylon, polyester, and rayon. The fabric may be made of one type of fiber, or may be made of a blend of two or more types of fiber.
Examples of paper include, but are not limited to, plain paper, inkjet paper, art paper, coated paper, and cast paper. The inkjet paper may have an ink absorbing layer made of silica particles or alumina particles, or an ink absorbing layer made of a hydrophilic polymer having a hydroxyl group such as polyvinyl alcohol.
Examples of plastics include, but are not limited to, films or plates of plastics such as polyvinyl chloride, polyethylene, polypropylene, polyethylene terephthalate, polycarbonate, polystyrene, and polyurethane.
There are no particular restrictions on the plastics used to coat the paper substrate, but examples include polyvinyl chloride, polyethylene, polypropylene, polyethylene terephthalate, polycarbonate, polystyrene, and polyurethane.
These recording media can be used singly or in combination of two or more.

In the case of using a recording medium made of plastic or a paper base material coated with plastics, it is preferable to use a recording medium that has undergone a treatment for introducing hydroxyl groups to the surface.
The treatment for introducing a hydroxy group is not particularly limited, but examples thereof include corona treatment and treatment for providing an ink-receiving layer with a material having a hydroxy group.
Materials having a hydroxy group include, but are not limited to, polyvinyl alcohol, starch, cellulose derivatives such as carboxymethylcellulose, casein, and gelatin. These materials can be used singly or in combination of two or more.

Heating step The inkjet recording method of the present embodiment preferably includes a heating step of heating the recording medium to a temperature higher than the reaction temperature between the hydroxy groups and the halogen atoms in the resin (A) at the same time as or after the ink adhesion step. Including further.
By including the heating step, hydroxyl groups on the surface of the recording medium react with residual halogen atoms in the resin (A), and the water-insoluble coloring material can be better fixed to the recording medium. The heating method is not particularly limited, but includes, for example, the HT method (high temperature steaming method), the HP method (high pressure steaming method), and the thermosol method.

In the heating step, the surface of the recording medium to which the ink composition is applied may or may not be subjected to pressure treatment. As a heating method that does not pressurize the surface of the recording medium on which the ink composition is adhered, oven drying (a method that does not use a press such as a conveyor oven or a batch oven) can be used. By including such a heating step, the productivity of recorded matter is further improved. The heating method for applying pressure to the surface of the recording medium on which the ink composition is adhered is not particularly limited, but examples thereof include heat press and wet-on-dry. The term "pressurization" refers to applying pressure to the recording medium by bringing a solid body into contact with the recording medium.

The temperature during the heat treatment is preferably 60° C. or higher, more preferably 60° C. or higher and 180° C. or lower, and still more preferably 60° C. or higher and 175° C., from the viewpoint of more effectively and reliably exhibiting the effects of the present invention. or less, and more preferably 60° C. or higher and 170° C. or lower.
When fabric is used as the recording medium, the temperature during heat treatment is preferably 100° C. or higher and 180° C. or lower, more preferably 130° C. or higher and 175° C., from the viewpoint of more effectively and reliably exhibiting the effects of the present invention. or less, more preferably 150° C. or higher and 170° C. or lower.
When using a recording medium made of plastic or a paper substrate coated with plastics, the temperature during the heat treatment is preferably 60° C. or higher from the viewpoint of more effectively and reliably exhibiting the effects of the present invention. The temperature is more preferably 60° C. or higher and 150° C. or lower, still more preferably 60° C. or higher and 140° C. or lower, and still more preferably 60° C. or higher and 130° C. or lower.

Washing Step When the recording medium is fabric, the inkjet recording method of the present embodiment may further include a washing step of washing the recording medium to which the ink composition has adhered after the heating step. The washing process can effectively remove the non-water-soluble coloring agent that is not dyed to the fibers. The washing step can be performed using water, for example, and soaping treatment may be performed as necessary. The soaping treatment method is not particularly limited, but includes, for example, a method of washing off unfixed pigment with a hot soap solution or the like.

In this way, it is possible to obtain a printed material such as a printed material on which an image derived from the ink composition is formed on a recording medium including fabric.

According to the present embodiment, a dispersion that exhibits excellent viscosity and provides an ink composition that exhibits excellent fastness to rubbing of a fixed image on a fabric and excellent abrasion resistance to a film, and an ink composition for inkjet recording using the same. , and an inkjet recording method can be provided.

Hereinafter, the present invention will be described more specifically using examples and comparative examples. The present invention is by no means limited by the following examples.

Synthesis of resin Synthesis example 1: Synthesis of resin 1 Sulfonic acid-modified polyvinyl alcohol (product name: Gohsenex (registered trademark) L-3266, manufactured by The Nippon Synthetic Chemical Industry Co., Ltd., saponification degree 85 mol%) was added to a 300 mL three-necked flask. 4.7 parts by mass (molar amount of hydroxy group: 0.079 mol part (molar amount 1.5 times that of the triazine compound)) and 85 parts by mass of water were added and cooled to 0°C. As a triazine compound, 10 parts by mass (0.054 mol part) of cyanuric chloride (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was gradually added and stirred for 30 minutes to obtain a suspension. After that, the temperature was raised to 60° C. and the reaction was carried out for 2 hours. After completion of the reaction, 100 parts by mass of an aqueous solution of resin 1 was obtained.

Synthesis Example 2: Synthesis of Resin 2 Sulfonic acid-modified polyvinyl alcohol (product name: Gohsenex (registered trademark) CKS-50, manufactured by The Nippon Synthetic Chemical Industry Co., Ltd., saponification degree 99 mol%) 4.7 parts by mass (hydroxy Mole amount of group: 0.11 mol part (twice the molar amount with respect to the triazine compound)) and 85 parts by mass of water were added and cooled to 0°C. As a triazine compound, 10 parts by mass (0.054 mol part) of cyanuric chloride (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was gradually added and stirred for 30 minutes to obtain a suspension. After that, the temperature was raised to 60° C. and the reaction was carried out for 2 hours. After completion of the reaction, 100 parts by mass of an aqueous solution of Resin 2 was obtained.

Synthesis Example 3: Synthesis of Resin 3 In a 300 mL three-necked flask, sulfonic acid-modified polyvinyl alcohol (product name: Gohsenex (registered trademark) L-3266, manufactured by The Nippon Synthetic Chemical Industry Co., Ltd., saponification degree 85 mol%) 2.4 parts by mass (hydroxy Mole amount of group: 0.041 mol part (0.76 times the molar amount with respect to the triazine compound)) and 85 parts by mass of water were added and cooled to 0°C. As a triazine compound, 8.1 parts by mass (0.054 mol part) of 2,4-dichloro-1,3,5-triazine (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was gradually added thereto and stirred for 30 minutes to form a suspension. Obtained. After that, the temperature was raised to 60° C. and the reaction was carried out for 2 hours. After completion of the reaction, 100 parts by mass of an aqueous solution of resin 3 was obtained.

Synthesis Example 4: Synthesis of Resin 4 4.7 parts by mass of cation (quaternary ammonium salt)-modified polyvinyl alcohol (Gohsenex (registered trademark) K-434, manufactured by The Nippon Synthetic Chemical Industry Co., Ltd., saponification degree 85 mol%) in a 300 mL three-necked flask (molar amount of hydroxy group: 0.079 mol part (molar amount 1.5 times that of the triazine compound)) and 85 parts by mass of water were added and cooled to 0°C. As a triazine compound, 10 parts by mass (0.054 mol part) of cyanuric chloride (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was gradually added and stirred for 30 minutes to obtain a suspension. After that, the temperature was raised to 60° C. and the reaction was carried out for 2 hours. After completion of the reaction, 100 parts by mass of an aqueous solution of resin 4 was obtained.

Synthesis Example 51: Synthesis of Resin 51 In a 300 mL three-necked flask, sulfonic acid-modified polyvinyl alcohol (product name: Gohsenex (registered trademark) L-3266, manufactured by The Nippon Synthetic Chemical Industry Co., Ltd., saponification degree 85 mol%) 2.4 parts by mass (hydroxy Mole amount of group: 0.041 mol part (molar amount 0.76 times that of the triazine compound)) and 85 parts by mass of water were added and cooled to 0°C. 10 parts by mass (0.054 mol part) of monochlorotriazine was gradually added thereto and stirred for 30 minutes to obtain a suspension. After that, the temperature was raised to 60° C. and the reaction was carried out for 2 hours. After completion of the reaction, 100 parts by mass of an aqueous solution of resin 51 was obtained.

Preparation of Dispersion Example A1: Preparation of Dispersion 1 80 parts by mass of zirconia beads, 13 parts by mass of an aqueous solution of resin 1, and C.I. I. Pigment Blue 15:3 (hereinafter also referred to as “PB15:3”) 4 parts by mass, 1 part by mass of triethanolamine as a deoxidizing agent, and 17 parts by mass of pure water were added and pulverized in a bead mill for 1 hour. , as Dispersion 1.

Example A2: Preparation of Dispersion 2 80 parts by weight of zirconia beads, 13 parts by weight of an aqueous solution of resin 2, 4 parts by weight of PB15:3 as a water-insoluble colorant, and 1 part by weight of triethanolamine as a deoxidizing agent. and 17 parts by mass of pure water were added, and pulverized in a bead mill for 1 hour to prepare a dispersion liquid 2.

Example A3: Production of dispersion liquid 3 80 parts by mass of zirconia beads, 15 parts by mass of an aqueous solution of resin 3, and C.I. I. 4 parts by mass of Pigment Red 122 (hereinafter also referred to as “PR122”), 1 part by mass of triethanolamine as a deoxidizing agent, and 17 parts by mass of pure water were added and pulverized in a bead mill for 1 hour. and

Example A4: Production of dispersion liquid 4 80 parts by mass of zirconia beads, 10 parts by mass of aqueous solution of resin 1, polyurethane resin (product name: Ucoat (registered trademark) UX-485, solid content concentration: 40% by mass, Sanyo Kasei Kogyo Co., Ltd. (hereinafter simply referred to as “UX-485”)) 3 parts by mass, 4 parts by mass of PB15:3 as a water-insoluble coloring material, 1 part by mass of triethanolamine as a deoxidizing agent, 17 parts by mass of pure water was added thereto, and pulverized with a bead mill for 1 hour to prepare a dispersion liquid 4.

Example A5: Production of dispersion liquid 5 80 parts by mass of zirconia beads, 10 parts by mass of aqueous solution of resin 4, and polyurethane resin (product name: Ucoat (registered trademark) UX-485, solid content concentration: 40% by mass, Sanyo Kasei Kogyo Co., Ltd.), 4 parts by mass of carbon black (hereinafter also referred to as "CB") as a water-insoluble colorant, 1 part by mass of triethanolamine as a deoxidizing agent, and 17 parts by mass of pure water. was added and pulverized in a bead mill for 1 hour to obtain a dispersion liquid 5.

Example A6 Preparation of Dispersion 6 An aqueous solution of resin 2 was used in place of the aqueous solution of resin 1 in example A1, and C.I. I. Pigment Yellow 180 (hereinafter also referred to as “PY180”) is used, and a polyurethane resin (product name: Uriano (product name: Uriano Dispersion 6 was obtained in the same manner as Dispersion 1, except that W600 (registered trademark) manufactured by Arakawa Chemical Industries, Ltd. (hereinafter also simply referred to as "W600") was used.

Comparative Example A1: Production of Dispersion Liquid 51 The same method as in Example A1 except that polyvinyl alcohol (hereinafter also referred to as "PVA") was used instead of the aqueous solution of Resin 1, and monofunctional monochlorotriazine was used. A dispersion 51 was obtained.

Comparative Example A2: Production of Dispersion Liquid 52 Dispersion liquid 52 was obtained in the same manner as in Example A1, except that polyvinyl alcohol (hereinafter also referred to as "PVA") was used instead of the aqueous solution of Resin 1.

Comparative Example A3: Production of Dispersion Liquid 53 Dispersion liquid 53 was obtained in the same manner as in Example A1, except that an aqueous solution of resin 51 was used instead of the aqueous solution of resin 1.

Production of ink composition Examples B1 to B6, Comparative Examples B1 to B3
The components shown in Table 2 were mixed to obtain an ink composition.
The obtained ink composition was subjected to the following inkjet recording method and evaluated.

Evaluation method
Conditions of Inkjet Recording Method An ink cartridge is filled with each of the ink compositions obtained above, and an ink jet recording apparatus (product name: PX-G930, Seiko Epson Co., Ltd.) ejects ink from a recording head by the action of the energy of a piezo element. manufactured by the company). In the examples and comparative examples, the printing duty of a solid image printed under the condition that one ink droplet having a mass of 28 ng±10% per droplet is applied to a unit area of 1/600 inch×1/600 inch. is defined as 100%. The recording conditions were temperature: 23° C. and relative humidity: 55%.

Viscosity The obtained ink composition was measured at 25° C. with an E-type viscometer (product name: TVE-22, manufactured by Toki Sangyo Co., Ltd.), and the dispersibility was evaluated according to the following criteria based on the magnitude of the viscosity. The shear rate during measurement was set to 1 (1/s) and 1000 (1/s).
(Evaluation criteria)
A: Both viscosities at shear rates of 10 (1/s) and 1000 (1/s) are less than 0.005 Pa s B: Viscosities at shear rates of 10 (1/s) and 1000 (1/s) are both 0.005 Pa s or more and less than 0.01 Pa s C: Both viscosities at shear rates of 10 (1/s) and 1000 (1/s) are 0.01 Pa s or more and less than 0.02 Pa s D: At least one of 0.02 Pa s or more and less than 0.03 Pa s at shear rates of 10 (1/s) and 1000 (1/s) E: Shear rates of 10 (1/s) and 1000 ( 1/s) at least one of 0.03 Pa s or more

Rubbing fastness (cloth)
By an inkjet recording method using an inkjet recording device (product name: PX-G930, manufactured by Seiko Epson Corporation) modified machine (having a fabric fixing means so that recording on the fabric is possible) for the fabric, Each ink composition was deposited. As for the recording conditions, a solid image was recorded with an adhesion amount of 15 mg/inch ² . In this way, ink jet recording was performed on the fabric. Here, a "solid image" means an image in which dots are printed on all pixels that are the minimum printing unit area defined by the printing resolution.
After that, heat treatment was performed at 160° C. for 1 minute using a heat press to fix the ink composition on the fabric. In this way, a printed material was produced in which the fabric was imaged (printed with ink).
For each printed material, a Gakushin type rubbing fastness tester (product name: AB-301, manufactured by Tester Sangyo Co., Ltd.) is used, and 100 reciprocations are performed under a load of 200 g and a speed of 10 cm / s. After that, JIS color fastness test white cloth (JIS L 0803: 2011 compliant No. 3-1) was used to measure the dye transfer density optical density value (hereinafter also referred to as "dye transfer density OD value"), and the following The rubbing fastness was evaluated according to the evaluation criteria of The lower the dye migration density OD value, the better the fastness to rubbing. Table 2 shows the results.
Evaluation Criteria A: The dye migration density OD value is 0.15 or less.
B: The dye migration density OD value is more than 0.15 and 0.20 or less.
C: The dye migration density OD value is more than 0.20 and 0.25 or less.
D: The dye migration density OD value is more than 0.25 and 0.30 or less.
E: The dye migration density OD value is over 0.3.

Scratch resistance test (film)
Using the above-mentioned inkjet recording apparatus, a 1.0-inch×0.05-inch print with a recording duty of 100% was applied to a corona-treated biaxially oriented polypropylene film (product name: OPP plain roll 25 μm thick, manufactured by Toyobo Co., Ltd.). A recorded matter having a solid pattern image of 5 inches was obtained. Printing was performed at a platen temperature of 60° C. and a dot density of 1440 dpi×1440 dpi. One day after the recording, each solid image on the recording was evaluated by pressing a cotton cloth. The evaluation was performed based on JIS L0849:2013 using a Gakushin scratch resistance evaluation device (product name: AB-301, manufactured by Tester Sangyo Co., Ltd.) under the condition of 100 reciprocations under a 200 g load. After that, staining of the gold cloth cotton, staining of the non-recording area, and peeling of the printed area were visually observed, and the scratch resistance was evaluated according to the evaluation criteria shown in the table. Table 2 shows the results.
Evaluation Criteria A: There was almost no stain on the gold cloth cotton and stain on the non-recorded area, and there was almost no peeling of the printed area.
B: There was little staining of gold cloth cotton and staining in the non-recording area, but there was almost no peeling of the printed area.
C: There was staining of gold cloth cotton and staining in the non-recording area, and there was some peeling of the printed area.
D: There was considerable staining of the gold cloth cotton and staining in the non-recorded area, and the printed area was peeled off to a large extent.

BYK-348: Silicone surfactant (product name: BYK-348, manufactured by BYK-Chemie Japan Co., Ltd.)
CMC: carboxymethyl cellulose

From the above evaluation results, it can be seen that the dispersion liquids and ink compositions of Examples are superior to the dispersion liquids and ink compositions of Comparative Examples in dispersibility, fastness to rubbing against fabrics, and abrasion resistance.

Claims (10)

a resin synthesized from a modified polyvinyl alcohol into which an anionic group or a cationic group has been introduced; and a triazine compound having three halogen atoms or 2,4-dichloro-1,3,5-triazine ;
a water-insoluble coloring material;
water and,
contains
Let a be the number of halogen atoms in one molecule of the triazine compound, x (mol) be the molar amount of the triazine compound, and y (mol) be the molar amount of the hydroxyl group (OH group) of the modified polyvinyl alcohol. A dispersion that satisfies the formula (1a) of
0.5≦(x×ay)/x≦2.0 (1a) 2. The dispersion of claim 1, wherein said resin has residual halogen atoms derived from said triazine compound. 3. The dispersion according to claim 1 or 2, wherein the triazine compound is a triazine compound having 3 halogen atoms. 4. The dispersion according to any one of claims 1 to 3, further comprising a polyurethane resin containing an active hydrogen group. The dispersion according to any one of claims 1 to 4, wherein the resin is synthesized by reacting the modified polyvinyl alcohol and the triazine compound at a temperature of 50°C or higher and lower than 70°C. An ink composition for inkjet recording, comprising the dispersion according to any one of claims 1 to 5. An ink jet recording method, comprising an ink adhesion step of ejecting the ink composition according to claim 6 from a recording head to adhere it to a recording medium. 8. The inkjet recording method according to claim 7, wherein the recording medium has a hydroxyl group on its surface. 9. The inkjet recording method according to claim 8, further comprising a heating step of heating the recording medium to a reaction temperature of the hydroxyl groups and the halogen atoms in the resin or higher, simultaneously with or after the ink applying step. The inkjet recording method according to claim 9, wherein the heating temperature in the heating step is 60°C or higher.