JP2023128723A - Inkjet ink composition, inkjet recording method, and recorded material - Google Patents

Abstract

To provide an inkjet ink composition that includes a biological chromatic color material and has excellent color development, storage stability, and discharge stability.SOLUTION: An aqueous inkjet ink composition includes a biological, water-insoluble chromatic color material, and a biological dispersant. The chromatic color material is dispersed in the ink composition by means of the dispersant.SELECTED DRAWING: None

Description

The present invention relates to an inkjet ink composition, an inkjet recording method, and a recorded matter.

Inkjet recording is a method of recording by ejecting small droplets of an inkjet ink composition from fine nozzles and making them adhere to a recording medium. This method has the feature that high-resolution and high-quality images can be recorded at high speed with a relatively inexpensive device. On the other hand, in recent years, there have been concerns about environmental issues such as the impact of floating plastics on the ecosystem and carbon dioxide emissions caused by the use of fossil fuels and other petroleum-derived materials. Ink compositions are being developed that take environmental issues into consideration by using materials derived from these materials.

Examples of naturally-derived chromatic coloring materials are known, such as Indian indigo, lac pigment, and turmeric pigment. material is required. As such chromatic coloring materials, mainly water-soluble ones are known, but they have a problem of poor color development. Therefore, ink compositions with excellent color development properties are being considered, such as by using naturally-derived chromatic coloring materials in combination with other materials.

For example, in Patent Document 1, the purpose is to improve the color development of a pigment compound derived from a red beetle by using a combination of pigment compounds derived from safflower, and to provide a color development improving agent that exhibits a fresh and vivid red color. A color development improving agent containing a pigment compound derived from red beetles as an active ingredient is disclosed.

Japanese Patent Application Publication No. 2004-292628

However, Patent Document 1 does not mention anything about the problem of color development that naturally derived and water-soluble chromatic coloring materials have, and also There is also no mention of improving storage stability and ejection stability by using a predetermined naturally derived dispersant.

The inkjet ink composition of the present invention is an aqueous inkjet ink composition containing a biologically derived water-insoluble chromatic colorant and a biologically derived dispersant, wherein the chromatic colorant comprises: This is an inkjet ink composition that is dispersed in the ink composition using the above dispersant.

Further, the inkjet recording method of the present invention is an inkjet recording method including an ink adhesion step of ejecting the above ink composition from an inkjet head and adhering it to a recording medium.

Furthermore, the recorded matter of the present invention is a recorded matter to which the above ink composition is attached.

1 is a schematic diagram of an example of a recording device that can be used in this embodiment.

Hereinafter, embodiments of the present invention (hereinafter referred to as "this embodiment") will be described in detail with reference to the drawings as necessary, but the present invention is not limited thereto, and the gist thereof Various modifications are possible without departing from the above. In addition, in the drawings, the same elements are given the same reference numerals, and overlapping explanations will be omitted. In addition, the positional relationships such as top, bottom, left, and right are based on the positional relationships shown in the drawings unless otherwise specified. Furthermore, the dimensional ratios in the drawings are not limited to the illustrated ratios.

1. Inkjet Ink Composition The inkjet ink composition of the present embodiment (hereinafter also simply referred to as "ink composition") is a water-based inkjet ink composition that is biologically derived and contains a water-insoluble chromatic coloring material. , a biologically derived dispersant, and the chromatic coloring material is dispersed in the ink composition by the dispersant.

In this embodiment, the inkjet ink composition refers to an ink composition that is used by being ejected from an inkjet head by an inkjet method and attached to a recording medium.

2. Description of the Related Art Ink compositions using coloring materials derived from natural products are being developed as inks that are environmentally friendly. Traditionally, water-soluble colorants have generally been used as naturally-derived chromatic colorants used in color inks, as there is no need to use dispersants; There is a problem that color development is poor. On the other hand, it is known that water-insoluble chromatic coloring materials tend to have excellent coloring properties, but in order to be used in water-based ink compositions, it is necessary to use water-insoluble chromatic coloring materials while maintaining these coloring properties. There is a need for a dispersant that can stably disperse coloring materials in ink and improve storage stability and ejection stability.

In this embodiment, the water-insoluble chromatic coloring material is added to the water-based ink composition by using a predetermined biologically-derived dispersant while improving the coloring property of the biologically-derived and water-insoluble chromatic coloring material in the aqueous system. It can be dispersed into a wide variety of materials, and storage stability and discharge stability can be ensured. Furthermore, since a biologically derived dispersant is used as the above-mentioned dispersant, it is also excellent in environmental friendliness.

The components, physical properties, manufacturing method, etc. of the ink composition according to this embodiment will be explained in detail below.

1.1. Chromatic coloring material The chromatic coloring material in this embodiment is not particularly limited as long as it is biologically derived and water-insoluble, but examples include flavonoid pigments, quinoid pigments, carotenoid pigments, and other natural pigments. Examples include pigments that originate from substances. Note that even if the same biologically derived coloring material is used, there can be both water-soluble and water-insoluble coloring materials.

Flavonoid pigments include, but are not particularly limited to, water-insoluble safflower pigments, turmeric pigments, and the like. Quinoid pigments are not particularly limited, but include, for example, water-insoluble cochineal pigments, lac pigments, madder pigments, and the like. Carotenoid pigments include, but are not particularly limited to, water-insoluble gardenia pigments, capsicum pigments, annatto pigments, and the like. Other pigments originating from natural products include, but are not particularly limited to, water-insoluble moss pigment, Indian indigo, beetlet, and the like. The chromatic coloring materials may be used alone or in combination of two or more.

Among these, it is preferable to include a chromatic coloring material derived from at least one selected from the group consisting of Indian indigo, lac pigment, turmeric pigment, and safflower pigment. Inclusion of such a chromatic coloring material tends to improve color development, and also tends to improve storage stability and ejection stability when using the dispersant of the present embodiment described later.

In this embodiment, chromatic color refers to a test pattern in which ink is applied to a white recording medium such as high-quality paper with the minimum amount of ink that can be applied to the entire surface of the recording medium. This means that CIELAB colorimetry is performed using a colorimeter, and the color saturation (C* value) is 1.0 or more. That is, vegetable charcoal whose saturation is 0, such as white, black, and a color obtained by mixing white and black, is not included in the chromatic coloring materials in this embodiment.

Here, water-insoluble means that when the chromatic coloring material is dissolved in water at 20° C., the amount dissolved in 100 g of water is 0.1 g or less. On the other hand, water-soluble means that when a chromatic coloring material is dissolved in water at 20° C., the amount dissolved in 100 g of water exceeds 0.1 g. In these tests, "dissolve" means that the entire solution does not appear cloudy or that no insoluble matter is visible, at least visually.

The chromatic coloring materials exemplified above may be commercially available with the same name for multiple derivatives with different chemical structures, and some of them are water-soluble coloring materials and others are water-soluble. Although both water-insoluble colorants may be included, all chromatic colorants in this embodiment mean water-insoluble colorants.

Moreover, biological origin may be plant-derived or animal-derived. Here, fossil fuels such as petroleum can also be said to be biologically derived if their origins are traced, but in this embodiment, fossil fuels are not included in biologically derived substances. By using biologically-derived ingredients instead of fossil fuel-derived ingredients, it is possible to reduce environmental impact and also contribute to carbon dioxide reduction.

The chromatic coloring material of this embodiment preferably has at least one of a hydroxyl group and a carboxyl group in its molecular structure. Such chromatic coloring materials are not particularly limited, but include, for example, the chromatic coloring materials specifically exemplified above. As a result, it tends to have excellent interaction with the naturally-derived dispersant described below, and to have excellent storage stability and ejection stability. Note that vegetable charcoal, which is the main non-chromatic coloring material, does not include a hydroxyl group or a carboxyl group in its molecular structure, and therefore is not included in the chromatic coloring materials of this embodiment. Note that coloring materials having a hydroxyl group and a carboxyl group have a higher affinity with biologically derived dispersants, and tend to have better storage stability and ejection stability.

The volume average particle diameter D ₅₀ corresponding to a cumulative degree of 50% of the chromatic coloring material is preferably 20 to 600 nm, more preferably 50 to 500 nm, still more preferably 80 to 400 nm, even more preferably It is 120 to 200 nm. When the volume average particle diameter D ₅₀ of the chromatic coloring material is within such a range, it tends to be particularly excellent in storage stability and ejection stability. Note that the "volume average particle diameter _D50 " refers to the particle diameter when the integrated value from small particle diameters reaches 50% of the total in the volume-based cumulative distribution of particle diameters.

The volume average particle diameter D ₉₀ of the chromatic coloring material is preferably 100 to 1000 nm, more preferably 150 to 500 nm, and still more preferably 200 to 300 nm. When the volume average particle diameter D ₉₀ of the chromatic coloring material is within such a range, it tends to be particularly excellent in storage stability and ejection stability. Note that the "volume average particle diameter D ₉₀ " refers to the particle diameter when the integrated value from small particle diameters reaches 90% of the total in the volume-based cumulative distribution of particle diameters.

The ratio of the volume average particle diameter D ₉₀ of the chromatic coloring material to the volume average particle diameter D ₅₀ of the chromatic coloring material (D ₉₀ /D ₅₀ ) is preferably 1.2 or more, more preferably 1.2 or more. It is 2.0 or less, more preferably 1.4 or more and 1.8 or less. When D ₉₀ /D ₅₀ is within such a range, storage stability and ejection stability tend to be especially excellent.

The content of the chromatic coloring material is preferably 3.0 to 15% by mass, more preferably 6.0 to 13% by mass, even more preferably 9.0 to 13% by mass, based on the total amount of the ink composition. It is 11% by mass. When the content of the chromatic coloring material is 3.0% by mass or more, color development tends to be excellent, and when the content of the chromatic coloring material is 15% by mass or less, storage stability and discharge stability are improved. They tend to be good at sex.

1.2. Dispersants Dispersants are not particularly limited as long as they are biologically derived, but examples include glycerin fatty acid esters, polyglycerin fatty acid esters, polyoxyethylene glycerin fatty acid esters, sucrose fatty acid esters, sorbitan fatty acid esters, and propylene glycol fatty acids. Examples include esters, lecithin, lecithin derivatives, enzyme-treated lecithin, Quillaja saponin, and polyoxyethylene alkyl ether. Among these, it is preferable to include at least one selected from the group consisting of polyglycerol fatty acid ester, sucrose fatty acid ester, and sorbitan fatty acid ester. As a result, it tends to have excellent interaction with the above-mentioned chromatic coloring materials, and in particular, to have excellent storage stability and ejection stability.

The content of the dispersant is preferably 1.0 to 20% by mass, more preferably 6.0 to 16% by mass, and even more preferably 9.0 to 12% by mass, based on the total amount of the ink composition. %. When the dispersant content is 1.0% by mass or more, storage stability tends to be excellent, and when the dispersant content is 20% by mass or less, discharge stability tends to be excellent.

Further, the ratio (B/A) of the content (B) of the dispersant to the content (A) of the chromatic coloring material is preferably 0.1 to 3.0, more preferably 0.4 to 2. .0, more preferably 0.7 to 1.2. When the ratio (B/A) of the content (B) of the dispersant to the content (A) of the chromatic coloring material is 0.1 or more, storage stability tends to be excellent, and the chromatic coloring material When the ratio (B/A) of the content (B) of the dispersant to the content (A) of the dispersant is 3.0 or less, color development tends to be excellent.

1.3. Water-soluble organic solvents Examples of water-soluble organic solvents include, but are not limited to, lower compounds such as methanol, ethanol, 1-propanol, isopropanol, 1-butanol, 2-butanol, isobutanol, and 2-methyl-2-propanol. Alcohols; polyols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, and glycerin; triethylene glycol monomethyl ether, triethylene glycol dimethyl ether, triethylene glycol Examples include glycol ethers such as ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, and dipropylene glycol monopropyl ether. Among these, polyols are preferably included, and glycerin is more preferably included. The water-soluble organic solvents may be used alone or in combination of two or more.

The content of the water-soluble organic solvent is preferably 1.0 to 20% by mass, more preferably 6.0 to 16% by mass, even more preferably 9.0 to 16% by mass, based on the total amount of the ink composition. It is 12% by mass.

1.4. Surfactant The ink composition of this embodiment may further contain a surfactant. Such surfactants include, but are not particularly limited to, acetylene glycol surfactants, silicone surfactants, and fluorine surfactants. The surfactants may be used alone or in combination of two or more.

Examples of the acetylene glycol surfactant include, but are not limited to, 2,4,7,9-tetramethyl-5-decyne-4,7-diol and 2,4,7,9-tetramethyl-5- selected from alkylene oxide adducts of decyne-4,7-diol and alkylene oxide adducts of 2,4-dimethyl-5-decyn-4-ol and 2,4-dimethyl-5-decyn-4-ol One or more types are preferred.

Examples of silicone surfactants include polysiloxane compounds, polyether-modified organosiloxanes, and the like.

Fluorosurfactants include, but are not particularly limited to, perfluoroalkyl sulfonates, perfluoroalkyl carboxylates, perfluoroalkyl phosphates, perfluoroalkyl ethylene oxide adducts, perfluoroalkyl betaines, and perfluoroalkyl betaines. Examples include fluoroalkylamine oxide compounds.

The content of the surfactant is preferably 0.1 to 2.0% by mass, more preferably 0.6 to 1.6% by mass, and even more preferably 0.0% by mass, based on the total amount of the ink composition. .9 to 1.2% by mass.

1.5. Water The content of water in the ink composition of the present embodiment is preferably 55 to 85% by mass, more preferably 60 to 80% by mass, even more preferably 65 to 80% by mass, based on the total amount of the ink composition. It is 75% by mass.

1.6. Other Components In addition to the above-mentioned components, the ink composition of the present embodiment includes one or more known components that can be used in conventional ink compositions, as long as the effects of the present invention are not impaired. May include. Such known components include, but are not limited to, solubilizing agents, viscosity modifiers, pH adjusters, antioxidants, preservatives, fungicides, corrosion inhibitors, and metal ions that affect dispersion. Examples include chelating agents, other additives, and solvents other than the water-soluble organic solvents mentioned above.

2. Preparation method of inkjet ink composition The inkjet composition in this embodiment preferably includes a first mixing step of mixing a chromatic coloring material and a dispersant to obtain a dispersion, and mixing the dispersion and other components. and a second mixing step. Moreover, in the first mixing step, it is preferable to perform a dispersion treatment on the mixed mixture using a bead mill. The beads used in this case are not particularly limited as long as they are publicly known, but among them, it is preferable to use zirconia beads with a relatively large specific gravity, and the particle size of the zirconia beads is preferably 1.0 mm or less. preferable. In addition, the time for performing the dispersion treatment is preferably 1 hour or more, more preferably 2 hours or more, and even more preferably 3 hours or more.

3. Inkjet Recording Method The inkjet recording method of this embodiment includes an ink adhesion step of discharging the ink composition of this embodiment from an inkjet head and adhering it to a recording medium, and a conveyance step of conveying the recording medium. Other steps may be included depending on the process. Note that the ink adhesion step and the conveyance step may be performed simultaneously or alternately.

3.1. Ink Adhesion Step In the ink adhesion step, the ink composition of this embodiment is ejected from an inkjet head to adhere to a recording medium. More specifically, the pressure generating means provided in the inkjet head is driven to cause the ink composition filled in the pressure generating chamber of the inkjet head to be ejected from the nozzle.

Examples of the inkjet head used in the ink adhesion process include a line head that performs recording using a line method, and a serial head that performs recording using a serial method.

In a line method using a line head, for example, an inkjet head having a width greater than the recording width of a recording medium is fixed to a recording apparatus. Then, the recording medium is moved along the sub-scanning direction (the conveyance direction of the recording medium), and in conjunction with this movement, ink droplets are ejected from the nozzles of the inkjet head, thereby recording an image on the recording medium.

In a serial method using a serial head, for example, an inkjet head is mounted on a carriage that is movable in the width direction of the recording medium. Then, the carriage is moved along the main scanning direction (the width direction of the recording medium), and in conjunction with this movement, ink droplets are ejected from the nozzles of the inkjet head, thereby recording an image on the recording medium.

3.2. Conveyance Process In the conveyance process, the recording medium is conveyed in a predetermined direction within the recording apparatus. More specifically, the recording medium is conveyed from the paper feed section to the paper discharge section of the recording apparatus using a conveyance roller or a conveyance belt provided within the recording apparatus. During the transport process, the ink composition ejected from the inkjet head adheres to the recording medium, forming a recorded matter. The conveyance may be carried out continuously or intermittently.

3.3. Recording Medium The recording medium used in this embodiment is not particularly limited, but includes, for example, absorbent or non-absorbent recording media.

4. Recorded Matter The recorded matter of this embodiment is a recorded matter in which the ink composition of this embodiment is deposited on a recording medium by using the above inkjet recording method. Since such a recorded matter is obtained using the above-mentioned ink composition, the ink on the recording medium has excellent coloring properties even though it is attached with a naturally-derived chromatic coloring material.

5. Inkjet Recording Apparatus As an example of an inkjet apparatus, FIG. 1 shows a perspective view of a serial printer. As shown in FIG. 1, the serial printer 20 includes a transport section 220 and a recording section 230. The conveyance unit 220 conveys the recording medium F fed to the serial printer to the recording unit 230, and discharges the recording medium after recording to the outside of the serial printer. Specifically, the conveyance unit 220 has respective feed rollers, and conveys the fed recording medium F in the sub-scanning direction T1.

The recording unit 230 also includes a carriage 234 on which an inkjet head 231 having a nozzle for discharging an ink composition onto the recording medium F sent from the conveyance unit 220 is mounted, and a carriage 234 in the main scanning direction S1 of the recording medium F. , S2.

In the case of a serial printer, the inkjet head 231 is provided with an inkjet head whose length is smaller than the width of the recording medium, and the inkjet head moves to perform recording in multiple passes (multipass). Further, in the serial printer, an inkjet head 231 is mounted on a carriage 234 that moves in a predetermined direction, and the inkjet head moves with the movement of the carriage, thereby ejecting the ink composition onto the recording medium. As a result, recording is performed using two or more passes (multipass). Note that the pass is also referred to as main scanning. Between passes, sub-scanning is performed to convey the print medium. In other words, main scanning and sub-scanning are performed alternately.

Further, the inkjet device of this embodiment is not limited to the above-mentioned serial type printer, but may be the above-mentioned line type printer. A line-type printer is a printer that prints on a print medium in one scan using a line head, which is an inkjet head having a length equal to or longer than the print width of the print medium.

1. Preparation of Inkjet Ink Composition A coloring material dispersion liquid is prepared by mixing a water-insoluble coloring material, a dispersing agent, and a portion of water so as to have the composition shown in Tables 1 and 2. Then, put it in a container, add other ingredients, mix and stir with a magnetic stirrer for 2 hours, and then stir for 1 hour with a disk type horizontal bead mill filled with zirconia beads with a diameter of 0.5 mm. Thorough mixing was achieved by performing a dispersion process. Thereafter, each ink composition shown in Tables 1 and 2 was obtained by filtration using a PTFE membrane filter. The numerical values listed in Tables 1 and 2 indicate mass % unless otherwise specified.

The materials shown in Tables 1 and 2 are as follows.
<Chromatic color materials>
・Water-insoluble turmeric pigment: “Turmeric Powder” manufactured by Japan Advanced Agri Co., Ltd.
・Water-insoluble Indian indigo: “Indian indigo powder” manufactured by Aikuma Dye Co., Ltd.
・Water-insoluble lac pigment: “Hi Red S” manufactured by Daiwa Kasei Co., Ltd.
・Water-insoluble safflower pigment: “Casama Red F-HC” manufactured by Kiriya Chemical Co., Ltd.
<Water-soluble coloring material>
・Water-soluble gardenia blue pigment: “Kiriyasu Blue” manufactured by Kiriya Chemical Co., Ltd.
・Water-soluble turmeric pigment: “Wiener Yellow Conch” manufactured by Kiriya Chemical Co., Ltd.
<Dispersant>
・Decaglycerin lauric acid monoester (derived from vegetable oil)
・Sucrose stearate (derived from vegetable oil)
・Sorbitan caprylic acid ester (derived from vegetable oil)
・Polyoxyethylene alkyl ether (derived from vegetable oil)
<Petroleum-derived dispersant>
・Naphthalenesulfonic acid formalin condensate (petroleum derived)
<Mordant>
・Ferrous sulfate <water-soluble organic solvent>
・Glycerin <surfactant>
・"Olfine E1010" manufactured by Nissin Chemical Industry Co., Ltd.

2. Evaluation method 2.1. Color development evaluation The ink composition prepared above was filled into an ink cartridge of EPSON PX-S840 (serial inkjet printer), and a recording medium (A4 size Xerox P paper, Fuji Xerox copy paper, basis weight 64 g) was filled with the ink composition prepared above. /m ² , paper thickness 88 μm), a solid pattern was printed at Duty: 100% (the amount of ink adhering to completely fill the recording medium surface with ink) in an environment of a temperature of 25° C. and a humidity of 50%.

The OD value of the solid pattern of the obtained recorded material was measured using a colorimeter (Xrite i1, manufactured by Xrite), and the color development was evaluated according to the following evaluation criteria.
〔Evaluation criteria〕
A: OD value is 1.0 or more.
B: OD value is 0.8 or more and less than 1.0.
C: OD value is 0.6 or more and less than 0.8.
D: OD value is less than 0.6.

2.2. Storage Stability Evaluation The ink composition prepared above was placed in a screw tube and left standing at 60° C. for 5 days with the lid on. The initial viscosity at 20°C before standing and the viscosity at 20°C after standing for 5 days were measured, the rate of change in viscosity was calculated, and the storage stability was evaluated according to the following evaluation criteria.
〔Evaluation criteria〕
A: The viscosity change rate is less than 5%.
B: The viscosity change rate is 5% or more and less than 10%.
C: The viscosity change rate is 10% or more and less than 15%.
D: The viscosity change rate is 15% or more.

2.3. Ejection stability evaluation An ink cartridge of EPSON PX-S840 (serial inkjet printer) was filled with the ink composition prepared above, and a recording medium (A4 size Xerox P paper, Fuji Xerox copy paper, basis weight 64 g/m ² , paper thickness 88 μm), a solid pattern was printed on 100 sheets under an environment of temperature 25°C and humidity 50%, Duty: 5% (the amount of ink adhesion that completely filled the surface of the recording medium with ink). Printed.
After printing was completed, a nozzle check pattern was printed, and the number of nozzles that failed to eject out of the total number of 360 nozzles was counted.
〔Evaluation criteria〕
A: The number of nozzles with no ejection is less than 10.
B: The number of nozzles with no ejection is 10 or more and less than 30.
C: The number of nozzles failing to eject is 30 or more and less than 50.
D: The number of nozzles with ejection failure is 50 or more.

3. Evaluation Results According to a comparison between Examples 1 to 11 and Comparative Examples 1 to 5, the ink composition according to the present embodiment is superior to the ink compositions according to Comparative Examples 1 to 5, which do not satisfy the constituent requirements of the ink composition. It was found that the color development, storage stability, and ejection stability were superior compared to the above.

20... Serial printer, 220... Conveyance section, 230... Recording section, 231... Inkjet head, 234... Carriage, 235... Carriage movement mechanism, F... Recording medium, S1, S2... Main scanning direction, T1... Sub-scanning direction

Claims (11)

A water-based inkjet ink composition,
A biologically derived, water-insoluble chromatic coloring material,
A biologically derived dispersant;
the chromatic coloring material is dispersed in the ink composition by the dispersant;
Inkjet ink composition. The chromatic coloring material includes a chromatic coloring material derived from at least one selected from the group consisting of Indian indigo, lac pigment, turmeric pigment, and safflower pigment.
The inkjet ink composition according to claim 1. The dispersant contains at least one selected from the group consisting of polyglycerol fatty acid ester, sucrose fatty acid ester, and sorbitan fatty acid ester.
The inkjet ink composition according to claim 1 or 2. The chromatic coloring material has at least one of a hydroxyl group and a carboxyl group in its molecular structure,
The inkjet ink composition according to any one of claims 1 to 3. The volume average particle diameter D ₅₀ of the chromatic coloring material is 20 to 600 nm.
The inkjet ink composition according to any one of claims 1 to 4. The ratio of the volume average particle diameter D ₉₀ of the chromatic coloring material to the volume average particle diameter D ₅₀ of the chromatic coloring material (D ₉₀ /D ₅₀ ) is 1.2 or more;
The inkjet ink composition according to any one of claims 1 to 5. The content of the chromatic coloring material is 3.0 to 15% by mass based on the total amount of the ink composition.
The inkjet ink composition according to any one of claims 1 to 6. The ratio (B/A) of the content (B) of the dispersant to the content (A) of the chromatic coloring material is 0.1 to 3.0.
The inkjet ink composition according to any one of claims 1 to 7. a first mixing step of mixing the coloring material and the dispersant to obtain a dispersion;
A second mixing step of mixing the dispersion liquid and other components,
The inkjet ink composition according to any one of claims 1 to 8. An ink adhesion step of ejecting the ink composition according to any one of claims 1 to 9 from an inkjet head and adhering it to a recording medium,
Inkjet recording method. The ink composition according to any one of claims 1 to 9 is attached on a recording medium,
Recorded material.