JP2020121510A - Inkjet recording method - Google Patents

Abstract

To provide an inkjet recording method exerting excellent adhesion between a swellable recording medium after ink adhesion and a laminate film.SOLUTION: The inkjet recording method includes: an ink-sticking process of sticking an ink composition to a swellable recording medium by discharging the ink composition from an inkjet head; a laminate processing process of coating a surface of the swellable recording medium with a laminate film, where the ejection amount of each constituent contained in the ink composition in the ink-sticking process satisfies a condition represented by the following formula (1): X×0.35+Y≤1.56 (1). In the formula, X is an ejection amount per unit area (unit: mg/inch) of a total organic solvent excluding a compound having 3 hydroxyl groups contained in the ink composition, and a dye, and Y is an ejection amount per unit area (unit: mg/inch) of a compound having 3 hydroxyl groups contained in the ink composition (excluding a compound having nitrogen).SELECTED DRAWING: None

Description

The present invention relates to an inkjet recording method.

The inkjet recording method is capable of recording high-definition images with a relatively simple device, and is rapidly developing in various fields. Among them, when a recording medium such as a plastic film is used as the recording medium, the surface has a low affinity for the plastic film with the ink composition which is water-based, and therefore the surface has a swelling property containing a hydrophilic component. A recording medium may be used.

Then, a method in which an ink composition is deposited on a recording medium by inkjet recording to form an image and then the surface of the recording medium is covered with a laminate film is commercially used.

For example, as an example of an ink composition used in an inkjet recording method, Patent Document 1 discloses a water-based inkjet recording ink containing a colorant and water, the colorant being a pigment and a compound represented by the formula (1). A water-based ink for inkjet recording is described, which contains a dye represented by the formula and further contains a water-soluble resin.

JP, 2017-179258, A

When a swellable recording medium having a highly hydrophilic surface is printed with, for example, the ink composition described in Patent Document 1, sufficient adhesion can be obtained even if the surface of the recording medium is covered with a laminate film. However, there is a problem that the laminated film is easily peeled off.

The present inventors diligently studied to solve the above problems. As a result, they have found that the amount of the organic solvent applied in the ink composition affects the decrease in the adhesion between the swellable recording medium and the laminate film. Furthermore, it was found that glycerin among organic solvents strongly affects the adhesion. Then, they found that the above problems can be solved by adjusting the amount of each component contained in the ink composition to satisfy a predetermined condition, and completed the present invention.

That is, the present invention is as follows.
The ink jet recording method of the present invention comprises an ink adhering step of ejecting an ink composition from an ink jet head to adhere it to a swellable recording medium, and a laminating treatment step of coating the surface of the swellable recording medium with a laminate film. And the amount of each component contained in the ink composition in the ink application step satisfies the condition represented by the following formula (1).
X×0.35+Y≦1.56 (1)
(In the formula, X is the total amount of organic solvent other than the compound containing three hydroxyl groups contained in the ink composition and the amount of the dye per unit area (unit: mg/inch ² ), and Y is The amount (unit: mg/inch ² ) per unit area of the compound containing three hydroxyl groups (excluding the compound containing nitrogen) that can be contained in the ink composition.)

The material of the laminate film is preferably polypropylene or polyvinyl chloride.
The swellable recording medium preferably has an ink receiving layer, and the ink receiving layer contains polyvinyl alcohol, or inorganic particles and gelatin.
The duty in the ink adhering step is preferably 45% or more and 70% or less.
The ink composition preferably contains a compound having three hydroxyl groups, and the content of the compound having three hydroxyl groups is preferably 2.50% by mass or more and 7 or more with respect to the total amount of the ink composition. It is not more than 50% by mass.
The amount of the ink composition applied in the ink attaching step is 8.63 mg/inch ² or more and 13.43 mg/inch ² or less.

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

Inkjet recording method In the inkjet recording method of the present embodiment, an ink adhering step of ejecting an ink composition from an inkjet head to adhere it to a swellable recording medium, and laminating a surface of the swellable recording medium with a laminate film. And a processing step.
Then, the amount of each component contained in the ink composition in the ink attaching step satisfies the condition represented by the following formula (1).
X×0.35+Y≦1.56 (1)
Here, in the formula, X represents the total amount of organic solvent other than the compound containing three hydroxyl groups contained in the ink composition and the amount of the dye per unit area (unit: mg/inch ² ), and Y Is the implantation amount (unit: mg/inch ² ) per unit area of the compound containing three hydroxyl groups (excluding the compound containing nitrogen) that can be contained in the ink composition.
With the above configuration, the inkjet recording method of the present embodiment exhibits excellent adhesion between the swellable recording medium after ink is attached and the laminate film.

The inkjet recording method of the present embodiment is, for example, a recording method in which an ink composition is loaded into an inkjet device for use. The inkjet device is not particularly limited, and examples thereof include a drop-on-demand inkjet device. Examples of the drop-on-demand type inkjet device include a device adopting an inkjet printing method using a piezoelectric element provided in an inkjet head, and thermal energy generated by a heater of a heating resistance element provided in the inkjet head. An apparatus that employs an inkjet recording method that uses

Swellable recording medium The recording medium used in the inkjet recording method of the present embodiment is a swelling recording medium.
The "swellable hydrophilic recording medium" means a recording medium containing a hydrophilic component on the surface.
The hydrophilic component is not particularly limited, and examples thereof include polyvinyl alcohol (PVA), polyvinylpyrrolidone, polyethylene oxide, starch, cellulose derivatives (for example, carboxymethyl cellulose), casein, and gelatin. These hydrophilic components may be used alone or in combination of two or more.

The swellable recording medium is not particularly limited, and examples thereof include a recording medium made of a base material containing a hydrophilic component and a recording medium having an ink receiving layer containing a hydrophilic component and a base material.
When the swellable recording medium has an ink receiving layer, the ink receiving layer preferably contains inorganic particles. The inorganic particles are not particularly limited, but examples thereof include silica particles, alumina particles, zirconia particles, and titania particles.
Among the above, the ink receiving layer more preferably contains polyvinyl alcohol, or inorganic particles and gelatin.

The base material used for the swellable recording medium is not particularly limited, and examples thereof include paper and plastic.
The paper is not particularly limited, and examples thereof include plain paper, inkjet paper, art paper, coated paper, and cast paper.
The plastic is not particularly limited, and examples thereof include films or plates of plastics such as polyvinyl chloride, polyethylene, polypropylene, polyethylene terephthalate (PET), polycarbonate, polystyrene, and polyurethane.
The swellable recording medium is not particularly limited, and examples thereof include a backlit film.
Hereinafter, each step of the inkjet recording method of the present embodiment will be described in detail.

Ink Adhering Step In the ink adhering step of the present embodiment, for example, the ink composition is ejected from the inkjet head and adhered to the swellable recording medium. A conventionally known method can be used as an inkjet recording apparatus used in the ink attaching step. Among them, an apparatus that ejects droplets by utilizing the vibration of a piezoelectric element, that is, an apparatus that uses an inkjet head that forms ink droplets by mechanical deformation of an electrostrictive element can be mentioned.

Formula (1)
In the inkjet recording method of this embodiment, the amount of each component contained in the ink composition in the ink adhesion step satisfies the condition represented by the following formula (1).
X×0.35+Y≦1.56 (1)
In the formula, X is the total amount of organic solvent other than the compound containing three hydroxyl groups contained in the ink composition and the amount of dye per unit area (unit: mg/inch ² ), and Y is the ink composition. It is the implantation amount (unit: mg/inch ² ) per unit area of the compound containing three hydroxyl groups (excluding the compound containing nitrogen) that can be contained in the product.
By satisfying the condition represented by the formula (1), excellent adhesion is exhibited between the swellable recording medium after ink is attached and the laminate film.
Here, the X-implantation amount and the Y-implantation amount mean the ejection amount per unit area of each component on the entire printing surface of the swellable recording medium.
The amount of each component contained in the ink composition in the ink attaching step preferably satisfies the condition represented by the following formula (1a) from the viewpoint of further improving the adhesiveness, and is represented by the following formula (1b). It is more preferable that the above condition is satisfied, and it is further preferable that the condition represented by the following formula (1c) is satisfied.
X×0.35+Y≦1.55 (1a)
X×0.35+Y≦1.52 (1b)
X×0.35+Y≦1.47 (1c)

From the viewpoint of further improving color reproducibility, the amount of each component contained in the ink composition in the ink attaching step preferably satisfies the condition represented by the following formula (2a), and is represented by the following formula (2b). It is more preferable that the condition represented by the following is satisfied, and it is further preferable that the condition represented by the following formula (2c) is satisfied.
0.30≦X×0.35+Y (2a)
0.60≦X×0.35+Y (2b)
1.10≦X×0.35+Y... (2c)

The duty in the ink attaching step is not particularly limited, but is preferably 45% or more and 70% or less, more preferably 50% or more and 70% or less, and further preferably 55% or more and 70% or less. Even when the duty is within the range, the ink jet recording method of the present embodiment exhibits excellent adhesion between the swellable recording medium after ink is attached and the laminate film.

In the inkjet recording method of the present embodiment, the amount of the ink composition applied per unit area is not particularly limited, but is preferably 8.63 mg/inch ² or more and 13.43 mg/inch ² or less, and 9. more preferably 59 mg / inch ² or more 13.43mg / inch ² less, and more preferably 10.55mg / inch ² or more 13.43mg / inch ² or less. Even in the case where the amount of impact per unit area of the entire ink composition is within the range, in the inkjet recording method of the present embodiment, the swellable recording medium after ink adhesion and the laminate film are , Shows excellent adhesion.

Ink Composition The ink composition used in the present embodiment contains, for example, an organic solvent other than a compound having three hydroxyl groups and a dye.
The ink composition used in this embodiment may or may not contain a compound containing three hydroxyl groups, but preferably contains a compound containing three hydroxyl groups.
Examples of the compound containing three hydroxyl groups include trifunctional alcohols such as glycerin and trimethylolpropane. Since these compounds contain three hydroxyl groups, they are highly moisturizing. Furthermore, since the boiling point is high after the ink attaching step, it tends to remain on the swellable recording medium. When the amount of the ink composition ejected per unit area becomes large, the compound having three hydroxyl groups keeps the surface of the swellable recording medium moisturized when laminating the swellable recording medium after the ink attaching step. It is considered that the adhesion between the swellable recording medium after the ink is attached and the laminate film is lowered.
The compound containing nitrogen is excluded from the compound containing three hydroxyl groups.
On the other hand, when the compound containing three hydroxyl groups is contained in the ink composition, the recoverability of the clogging of the inkjet head is enhanced.
When the ink composition contains a compound having three hydroxyl groups, the content of the compound having three hydroxyl groups is from 2.50% by mass to 15.00% by mass based on the total amount of the ink composition. It is preferably 2.50 mass% or more and 10.00 mass% or less, more preferably 2.50 mass% or more and 7.50 mass% or less, and 2.50 mass% or more and 5. It is more preferable that the content is 00% by mass or less.

Dye The ink composition used in this embodiment is not particularly limited, and examples thereof include a yellow dye, a magenta dye, a cyan dye, and an orange dye.

The yellow dye is not particularly limited, and examples thereof include C.I. I. Acid Yellow 1, 3, 11, 17, 17, 19, 23, 25, 29, 36, 38, 40, 42, 44, 49, 59, 61, 70, 72, 75, 76, 78, 79, 98, 99, 110, 111, 127, 131, 135, 142, 162, 164, 165, C.I. I. Direct Yellow 1, 8, 11, 12, 24, 26, 27, 33, 39, 44, 50, 58, 85, 86, 87, 88, 89, 98, 110, 132, 142, 144, 162, 165, C. I. Reactive Yellow 1, 2, 3, 4, 6, 7, 11, 12, 13, 14, 15, 16, 17, 18, 22, 23, 24, 25, 26, 27, 37, 42, C.I. I. Food Yellow 3, 4, C.I. I. Solvent Yellow 15, 19, 21, 30, 109 may be mentioned. These yellow dyes can be used alone or in combination of two or more.

The magenta dye is not particularly limited, but examples thereof include C.I. I. Acid Red 1, 6, 8, 9, 13, 14, 18, 26, 27, 32, 35, 37, 42, 51, 52, 57, 75, 77, 80, 82, 85, 87, 88, 89, 92, 94, 97, 106, 111, 114, 115, 117, 118, 119, 129, 130, 131, 133, 134, 138, 143, 145, 154, 155, 158, 168, 180, 183, 184, 186, 194, 198, 209, 211, 215, 219, 249, 252, 254, 262, 265, 274, 282, 289, 303, 317, 320, 321, 322, C.I. I. Direct Red 1, 2, 4, 9, 11, 13, 17, 20, 23, 24, 28, 31, 33, 37, 39, 44, 46, 62, 63, 75, 79, 80, 81, 83, 84, 89, 95, 99, 113, 197, 201, 218, 220, 224, 225, 226, 227, 228, 229, 230, 231, C.I. I. Reactive Red 1, 2, 3, 4, 5, 6, 7, 8, 11, 12, 13, 15, 16, 17, 19, 20, 21, 22, 23, 24, 28, 29, 31, 32 , 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 45, 46, 49, 50, 58, 59, 63, 64, C.I. I. Sorbrise Red 1, C.I. I. Hood Red 7, 9, and 14 are mentioned. These magenta dyes can be used alone or in combination of two or more.

Examples of cyan dyes include C.I. I. Acid Blue 1, 7, 9, 15, 22, 23, 25, 27, 29, 40, 41, 43, 45, 54, 59, 60, 62, 72, 74, 78, 80, 82, 83, 90, 92, 93, 100, 102, 103, 104, 112, 113, 117, 120, 126, 127, 129, 130, 131, 138, 140, 142, 143, 151, 154, 158, 161, 166, 167, 168, 170, 171, 182, 183, 184, 187, 192, 199, 203, 204, 205, 229, 234, 236, 249, C.I. I. Direct Blue 1, 2, 6, 15, 22, 25, 41, 71, 76, 77, 78, 80, 86, 87, 90, 98, 106, 108, 120, 123, 158, 160, 163, 165, 168, 192, 193, 194, 195, 196, 199, 200, 201, 202, 203, 207, 225, 226, 236, 237, 246, 248, 249, C.I. I. Reactive Blue 1, 2, 3, 4, 5, 7, 8, 9, 13, 14, 15, 17, 18, 19, 20, 21, 25, 26, 27, 28, 29, 31, 32, 33 , 34, 37, 38, 39, 40, 41, 43, 44, 46, C.I. I. Sorbilize Bat Blue 1, 5, 41, C.I. I. Bat Blue 4, 29, 60, C.I. I. Food Blue 1, 2, C.I. I. Basic blue 9, 25, 28, 29, 44 can be mentioned. These cyan dyes can be used alone or in combination of two or more.

Examples of orange dyes include Acid Orange 3, 7, 8, 10, 19, 22, 24, 33, 45, 51, 51S, 56, 67, 74, 80, 86, 87, 88, 89, 94, 95. , 107, 108, 116, 122, 127, 140, 142, 144, 149, 152, 156, 162, 166, 168, direct orange 1, 6, 8, 10, 26, 27, 34, 39, 40, 46. , 49, 102, 105, 107, 118, Reactive Orange 1, 2, 4, 5, 7, 11, 12, 13, 15, 16, 20, 30, 35, 56, 64, 67, 69, 70, 72, 74, 82, 84, 86, 87, 91, 92, 93, 95, 107. These orange dyes can be used alone or in combination of two or more.

The content of the dye is preferably 1.00% by mass or more and 20.00% by mass or less based on 100% by mass of the entire ink composition, from the viewpoint of more effectively and reliably exhibiting the effects of the present invention. It is more preferably 0.000% by mass or more and 15.00% by mass or less, and further preferably 3.00% by mass or more and 10.00% by mass or less.

Organic solvent other than the compound containing three hydroxyl groups The ink composition used in the present embodiment may contain an organic solvent other than the compound containing three hydroxyl groups. The term “organic solvent” as used herein means an organic solvent that is in a liquid state at 20° C. and 1 atmospheric pressure. The organic solvent is not particularly limited as long as it is an organic solvent usually used as an ink component.

The organic solvent is a first organic solvent satisfying the following property (A) and a second organic solvent satisfying the following property (B) or (C), from the viewpoint of further suppressing the occurrence of aggregation unevenness and bleeding of the recorded image. It is preferable to include a solvent. A specific operation method (for example, a mixing ratio of polyvinyl alcohol and an organic solvent) for evaluating whether the organic solvent satisfies any of the following properties (A) to (C) is described in, for example, JP-A-2014. It may be performed according to the operation method described in JP-A-118509.
(A) When a mixture with polyvinyl alcohol is produced, a mass having a mass of 70% or more is generated with respect to the total mass of the mixture, and the mass is 5.3 g/mm ² or more and 7.1 g/ When a load of mm ² or less is applied, a mass having a mass of 90% or more with respect to the total mass of the mass is generated.
(B) When a mixture with polyvinyl alcohol is produced, a mass having a mass of 70% or more with respect to the total mass of the mixture is produced, and the mass is 5.3 g/mm ² or more and 7.1 g/mm or more. ^When a load of ² or less is applied, a mass having a mass of 90% or more of the total mass of the mass does not occur.
(C) When a mixture with polyvinyl alcohol is prepared, no lump having a mass of 70% or more is generated with respect to the total mass of the mixture.

In the ink composition used in this embodiment, the mass ratio (S1/S2) between the content (S1) of the first organic solvent and the content (S2) of the second organic solvent is 15.3 or more and 205 or less. It is preferable that it is 25.6 or more and 122.5 or less. When the mass ratio (S1/S2) is within the range, more excellent color reproducibility can be obtained.

The first organic solvent is not particularly limited, but examples thereof include 1,2-hexanediol, propylene glycol, 2-pyrrolidone, N-methyl-2-pyrrolidone, ethanol, ethylene glycol, and pentanediol. Further, as the first organic solvent, a commercially available product may be used, and examples of the commercially available product include Examide M100 (trade name, manufactured by Idemitsu Kosan Co., Ltd., amide solvent). These 1st organic solvents can be used individually by 1 type or in combination of 2 or more types.

The second organic solvent is not particularly limited, and examples thereof include diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, diethylene glycol monohexyl ether, diethylene glycol mono-2-ethylhexyl ether, tetraethylene glycol monohexyl ether, tetraethylene glycol. Mono 2-ethylhexyl ether, hexaethylene glycol mono 2-ethylhexyl ether, 2-methoxyethanol, diethylene glycol monobutyl ether, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, triethylene glycol monobutyl ether, dipropylene glycol monopropyl ether, ethylene glycol mono Examples thereof include ethyl ether and ethylene glycol monobutyl ether. These 2nd organic solvents can be used individually by 1 type or in combination of 2 or more types. Among these, the glycol ether having an alkyl group having 6 to 8 carbon atoms is preferably a glycol ether having an alkyl group having 6 to 8 carbon atoms, and more preferably diethylene glycol monohexyl ether. These glycol ethers have a high effect as a penetrating agent and can quickly permeate after adhering (landing) to the swellable recording medium, so that the effect of suppressing the aggregation unevenness is further enhanced, and more excellent color reproducibility can be obtained.

The solubility of the first organic solvent and the second organic solvent in 100 g of water at 20° C. is preferably 10 g or more, and more preferably 60 g or more. When the solubility is 10 g or more, the first organic solvent and the second organic solvent are well dissolved in water in the ink, and the compatibility between the first organic solvent and the second organic solvent is also good, and each component Separation is suppressed, and storage stability tends to be excellent.

The content of the first organic solvent is preferably 10.00% by mass or more and 40.00% by mass or less with respect to 100% by mass of the entire ink composition, from the viewpoint of obtaining more excellent color reproducibility. It is more preferably 0.000% by mass or more and 30.00% by mass or less, and further preferably 12.50% by mass or more and 20.00% by mass or less.

The content of the second organic solvent is preferably 0.10% by mass or more and 20.00% by mass or less with respect to 100% by mass of the entire ink composition, from the viewpoint of obtaining more excellent color reproducibility. 20 mass% or more and 10.00 mass% or less is more preferable, and 0.30 mass% or more and 8.00 mass% or less is further preferable.

The total content (S1+S2) of the first organic solvent and the second organic solvent is 12.00% by mass or more and 50.00% by mass with respect to 100% by mass of the entire ink composition, from the viewpoint of obtaining better color reproducibility. % Or less, preferably 15.00% by mass or more and 40.00% by mass or less, and more preferably 20.00% by mass or more and 35.00% by mass or less.

Water The water is not particularly limited, but for example, ion-exchanged water, ultrafiltered water, reverse osmosis water, pure water (eg, distilled water), and water from which ionic impurities have been removed as much as possible (eg, ultrapure water). Is mentioned. When water sterilized by irradiation with ultraviolet rays or addition of hydrogen peroxide is used, generation of mold and bacteria can be prevented when the ink is stored for a long time. The content of water is not particularly limited, and may be, for example, 50.00% by mass or more and 80.00% by mass or less based on 100% by mass of the entire ink composition.

The ink of this embodiment may further contain other components. Other components include, for example, a surfactant, a preservative or an antifungal agent, a chelating agent, and a rust preventive agent.

Surfactant The surfactant is not particularly limited, and examples thereof include nonionic surfactants.
The nonionic surfactant is not particularly limited, and examples thereof include a silicone surfactant and an acetylene glycol surfactant.

The silicone-based surfactant is not particularly limited, but examples thereof include BYK-306, BYK-307, BYK-333, BYK-341, BYK-345, BYK-346, BYK-348 (trade names, BYK Japan Japan. KF-351A, KF-352A, KF-353, KF-354L, KF-355A, KF-615A, KF-945, KF-640, KF-642, KF-643, KF-6020, X. -22-4515, KF-6011, KF-6012, KF-6015, KF-6017 (above brand name, Shin-Etsu Chemical Co., Ltd. make).

The acetylene glycol-based surfactant is not particularly limited, but for example, Surfynol 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, DF110D (these product names, manufactured by Air Products and Chemicals. Inc.), Olphin 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, SK-14, AE-3 (trade names, manufactured by Nisshin Chemical Industry Co., Ltd.), acetylenol E00, E00P, E40, E100 (trade names, Kawaken) Fine Chemical Co., Ltd.).

The content of the surfactant is not particularly limited, but may be, for example, 0.10% by mass or more and 2.00% by mass or less based on 100% by mass of the entire ink composition.

The preservative or antifungal agent is not particularly limited as the preservative or antifungal agent, and examples thereof include sodium benzoate, sodium pentachlorophenol, 2-pyridinethiol-1-oxide sodium, sodium sorbate, sodium dehydroacetate, and 1 , 2-benzisothiazolin-3-one. Examples of commercially available antiseptics or fungicides include Proxel XL2, Proxel GXL (trade names, manufactured by Avicia), Denide CSA, NS-500W (trade names, manufactured by Nagase ChemteX Corporation).

The content of the preservative or antifungal agent is not particularly limited, but may be, for example, 1.00% by mass or less based on 100% by mass of the entire ink composition.

Chelating agent The chelating agent is not particularly limited, and examples thereof include ethylenediaminetetraacetic acid or salts thereof (for example, disodium ethylenediaminetetraacetic acid disodium salt), 3-hydroxy-2,2'-iminodisuccinic acid or salts thereof ( Examples thereof include 3-hydroxy-2,2′-iminodisuccinate tetrasodium), iminodisuccinic acid or salts thereof (eg, tetrasodium iminodisuccinate).

The content of the chelating agent is not particularly limited, but may be, for example, 0.10% by mass or less based on 100% by mass of the entire ink composition.

Anti-rust agent The anti-rust agent is not particularly limited, and examples thereof include benzotriazole.

The content of the rust preventive agent is not particularly limited, but may be, for example, 0.10% by mass or less based on 100% by mass of the entire ink composition.

Laminating Process In the laminating process of this embodiment, the surface of the swellable recording medium is covered with a laminate film.
The laminating treatment step is, for example, a step of adhering a laminate film to the swellable recording medium to which the ink composition is attached, at least a portion of the swellable recording medium to which the ink composition is attached, through the ink attaching step. is there.

Laminated Film The laminated film used in the present embodiment includes at least a base material, for example.
The laminate film used in this embodiment may further include an adhesion layer and a layer exhibiting other functions.
The material of the substrate is not particularly limited, but examples thereof include polypropylene, polyethylene, polyethylene terephthalate, polyvinyl chloride (hereinafter, also referred to as “PVC”), polycarbonate, and polystyrene. Further, these materials may be imparted with uniaxial or polyaxial orientation by stretching or the like in the base material.
Among these base materials, polypropylene or polyvinyl chloride is preferable from the viewpoint of obtaining the effect of the present invention more remarkably.
The base material may contain additives such as a lubricant, an anti-blocking agent, a stabilizer, an antioxidant, an antistatic agent, an antifogging agent, and a coloring agent.
The thickness of the base material is not particularly limited, but is preferably 6 μm or more and 100 μm or less, and more preferably 7 μm or more and 40 μm or less.

The laminate film preferably has an adhesion layer containing a pressure sensitive adhesive or a thermoplastic resin.
Examples of the pressure-sensitive adhesive include acrylic pressure-sensitive adhesives.
The thermoplastic resin is not particularly limited, but for example, polypropylene, low density polyethylene, linear low density polyethylene, ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth ) Acrylic acid ester copolymers, ionomer resins, ethylene/α-olefin copolymers, polyolefin resins such as amorphous polyester, and polyester resins.
The thickness of the adhesion layer is not particularly limited, but may be, for example, 15 μm or more and 100 μm or less.

As a method of coating the surface of the swellable recording medium with a laminate film, a general method can be used. Examples of such a method include a method in which a swellable recording medium is sandwiched between laminate films, and the laminate is pressed by a press or a roller. At this time, when the adhesive layer contains a thermoplastic resin, it is preferable to heat it when pressure-bonding. When heating is performed, the temperature achieved by heating is preferably 40° C. or higher and 200° C. or lower.

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. The present invention is not limited to the following examples.

Examples 1 to 16 and Comparative Examples 1 to 4
An ink composition was prepared by mixing and dissolving the components shown in Table 1 below and filtering with a membrane filter having a pore size of 0.45 μm.
The ink compositions of Examples 1 to 16 and Comparative Examples 1 to 4 were filled in an ink jet printer (trade name “SC-B9080”, manufactured by Seiko Epson Corporation), and a swellable recording medium (trade name “PP- 130" manufactured by Flycenter Co., Ltd. was used to print a solid pattern that can be recorded at a duty of 70 to 30% shown in Table 1 at a resolution of 1440 dpi in the horizontal direction and 720 dpi in the vertical direction.
After printing the solid pattern, it was dried in a room temperature environment for 24 hours, and then laminated using a laminate film (material: PVC, manufactured by Flycenter).
The following evaluation tests were conducted and the results are shown in Table 1. In the table, C.I. I. Direct Blue 199 is a dye manufactured by Daiwa Kasei Co., Ltd.

The printed matter subjected to the adhesion laminating treatment was left for one day in an environment of a temperature of 40° C. and a relative humidity of 80%. Then, the printed solid pattern was formed with a width of 25 mm and a length of 100 mm, and was attached to one of two stainless steel flat plates (SUS304). A part of the pasted sample is overlaid on another SUS304 flat plate in a state of being stuck and 100 mm/min using a universal testing machine (trade name "Tensilon RTG-1250", A&D Co., Ltd.) The strength when the laminate film was peeled from the swellable recording medium was measured at the speed of, and the adhesion was evaluated according to the following criteria.
Evaluation criteria A: 2N or more B: 1N or more and less than 2N C: less than 1N

A clogging recovering inkjet printer (trade name “SC-B9080”, manufactured by Seiko Epson Corporation) was filled with the present ink composition, and left at 40° C. for 1 week with the cap open. After that, cleaning was performed to confirm how many times all nozzles returned, and the clogging recoverability was evaluated based on the following criteria.
Evaluation Criteria A: Return within 2 cleanings.
B: Returned after 3 to 5 cleanings.
C: Recovers after 6 cleanings or more, or does not recover.

Color reproduction (Gumut)
The ink compositions of Examples 1 to 16 and Comparative Examples 1 to 4 were filled in a cyan ink cartridge of an inkjet printer (trade name “SC-B9080”, manufactured by Seiko Epson Corporation), and the other cartridges were genuine products. Using a dedicated cartridge, a color chart image was printed on a swellable recording medium (trade name "PP-130", manufactured by Flycenter) at a resolution of 1440 dpi in the horizontal direction and 720 dpi in the vertical direction. The duty limit value at the time of printing is set to the value of each Example and Comparative Example. The obtained standard color chart image was measured for L ^* value, a ^* value, and b ^* value using a colorimeter (trade name "Xrite i1", manufactured by Xrite). The L ^* a ^* b ^* color reproduction range volume value (gamut value) was calculated from these values, and the color reproducibility was evaluated according to the following criteria.
Evaluation Criteria A: Gamut volume exceeds 60%.
B: The gamut volume is more than 50% and 60% or less.
C: Gamut volume is 50% or less.

As described above, it is understood from the results of Examples and Comparative Examples that excellent peel strength is exhibited by satisfying the condition of Expression (1).
Further, from the results of Examples, it is understood that the ink composition exhibits excellent clogging recovery property by containing the compound containing three hydroxyl groups.
From the results of the examples, it can be seen that the color reproducibility can be improved by setting the condition of Expression (1) to a value equal to or larger than a predetermined value.

Claims (6)

An ink attaching step of ejecting the ink composition from an inkjet head to attach the ink composition to a swellable recording medium;
A laminating step of coating the surface of the swellable recording medium with a laminating film,
Equipped with
The inkjet recording method, wherein the amount of each component contained in the ink composition in the ink attaching step satisfies the condition represented by the following formula (1).
X×0.35+Y≦1.56 (1)
(In the formula, X is the total amount of organic solvent other than the compound containing three hydroxyl groups contained in the ink composition and the amount of the dye per unit area (unit: mg/inch ² ), and Y is The amount (unit: mg/inch ² ) per unit area of the compound containing three hydroxyl groups (excluding the compound containing nitrogen) that can be contained in the ink composition.) The inkjet recording method according to claim 1, wherein the material of the laminate film is polypropylene or polyvinyl chloride. The swellable recording medium has an ink receiving layer,
The inkjet recording method according to claim 1, wherein the ink receiving layer contains polyvinyl alcohol, or inorganic particles and gelatin. The ink jet recording method according to claim 1, wherein the duty in the ink attaching step is 45% or more and 70% or less. The ink composition contains a compound containing three hydroxyl groups,
5. The content of the compound containing three hydroxyl groups is 2.50% by mass or more and 10.00% by mass or less with respect to the total amount of the ink composition. Inkjet recording method. The inkjet recording method according to any one of claims 1 to 5, wherein an applied amount of the ink composition in the ink attaching step is 8.63 mg/inch ² or more and 13.43 mg/inch ² or less.