JP2023089421A - Pretreatment liquid, aqueous inkjet ink set, and method for manufacturing printed matter - Google Patents

Abstract

To provide a pretreatment liquid for obtaining a printed matter which is excellent in base material adhesion, image quality, water resistance and scratch resistance in one-pass printer type inkjet printing, and a pretreatment liquid which has good adhesive force and appearance even after heat sterilization treatment of a printed matter.SOLUTION: A pretreatment liquid for one-pass printer type inkjet printing contains resin fine particles (A), a coagulant (B), and water, wherein the coagulant (B) contains a water-soluble cationic resin (C) having a structural unit derived from a vinyl monomer (c1) having a cationic group, in an elution curve when the whole water-soluble cationic resin (C) is measured by GPC, (1) an area ratio H/L in an elution curve of a high molecular weight component (H) to a low molecular weight component (L) with the molecular weight of 5,000 as a boundary is 75/25 to 97/3, and (2) a weight average molecular weight is 50,000 to 200,000.SELECTED DRAWING: None

Description

The present invention relates to a pretreatment liquid for one-pass printer type inkjet printing, a water-based inkjet ink set, and a method for producing a printed matter.

Unlike conventional plate printing such as offset printing, digital printing does not require plate making film or plate making, so it is possible to reduce costs and increase speed, and it is expected to become widespread in the future.

In the inkjet printing method, which is a type of digital printing, letters and images are obtained by directly ejecting ink droplets from extremely fine nozzles onto a printing substrate and attaching them to the printing substrate. The inkjet printing method has advantages such as low noise of the device used, good operability, and easy colorization, and is widely used as an output device in offices and homes. In addition, due to the improvement of inkjet technology, it is beginning to be used as a digital printing output machine in industrial applications.

Conventionally, solvent inks and UV inks have been used in inkjet printing methods for industrial applications. In recent years, however, the demand for water-based inks has increased from the viewpoint of environmental friendliness.

Water-based inks used in inkjet printing (hereinafter simply referred to as "inkjet") are conventionally used not only for highly permeable plain paper, but also for special papers with low permeation (e.g. coated paper, glossy photo paper). It was. That is, water is the main component, and a water-soluble organic solvent such as glycerin or glycol is added in order to control wettability and dryness with respect to highly permeable substrates. When a character or image pattern is printed on the base material using the water-based ink for inkjet including these liquid components, the liquid component permeates the base material, dries, and is fixed to obtain a printed matter. can be done.

The inkjet printing method is broadly divided into a serial printer method in which printing is performed while the inkjet head moves left and right with respect to the substrate, and a one-pass printer method in which the inkjet head is fixed and the substrate moves at high speed while printing. be done.

On the other hand, in the flexible packaging materials market, along with changes and diversification of consumer needs, there has been an increase in the variety of products and shortening of product cycles. There is a desire for ink-jet printing in a single-pass printer system. Moreover, high-speed printing is required to improve the productivity of printed matter. However, for a non-permeable substrate such as a film substrate, the ink droplets after landing do not penetrate into the substrate at all. The particles coalesce to cause blurring and unevenness, impairing the image quality.

As a measure for solving the above problems, a process of applying a pretreatment liquid onto a non-permeable substrate is known. In general, pretreatment liquids for water-based inkjet inks include those that form a layer (ink-receiving layer) that absorbs liquid components in the water-based inkjet ink and improves drying properties, and those that prevent aggregation of solid components and thickening of the ink. Two types are known, one of which is intentionally caused to form a layer (ink aggregation layer) that prevents bleeding and color unevenness between water-based inkjet ink droplets and improves image quality (Patent Documents 1 and 2). there is
Specifically, the ink-receiving layer is formed by coating a medium with a coating liquid containing an acrylic resin having a quaternary ammonium base to provide an ink-absorbing layer, and further coating the upper surface of the ink-absorbing layer. (Patent Documents 3 and 4). Further, Patent Document 5 describes an ink-receiving layer characterized by using a cationic resin obtained from an ethylenically unsaturated monomer in a method for producing an ink-jet recording medium in which an ink-receiving layer is provided on a support. Are listed.

However, in the case of the ink-receiving layer, for example, when a large amount of ink is received at one time, image cracking due to swelling of the ink-receiving layer, bleeding and color unevenness due to exceeding the acceptable amount, and ink component transfer to the receiving layer. Concentration loss due to absorption may occur. In the case of forming the receiving layer, it is necessary to make the thickness of the coating film of the pretreatment liquid for forming the ink receiving layer thicker than in the case of the ink aggregation layer described later.

In Patent Documents 3 to 5, since the coating film thickness is as large as several tens of microns, the drying property of the pretreatment liquid itself is lowered, and problems such as poor drying may occur. As described above, when used for a non-permeable base material such as a film base material, the pretreatment liquid does not permeate at all, so the above problems are likely to occur.

On the other hand, as an example of a pretreatment liquid for forming an ink aggregation layer, Patent Document 1 describes a pretreatment liquid containing a polyvalent metal salt and (cationized) hydroxyethyl cellulose and having a defined surface tension. It is said that by using the pretreatment liquid, a high-quality printed material with high image density, no bleeding, and excellent abrasion resistance can be obtained.

Here, when printing on a non-permeable base material such as a film base material used for flexible packaging materials, the ink droplets do not permeate and absorb into the base material after they land, so the ink is sufficient for the film base material. must have good adhesion. If the adhesion to the film substrate is insufficient, the ink film may peel off due to rubbing, etc., and when laminated with another film via an adhesive (laminating adhesive), a laminate is formed. The adhesive force between the layers to be laminated may not be obtained, and a peeling phenomenon (delamination) may occur between the layers.

Further, in the case of flexible packaging materials, after being shaped into a packaging material, it is often subjected to a thermal sterilization process such as boiling or retorting. Therefore, a tough ink film that can withstand this heat sterilization treatment is required, and in particular, resistance to water is required. This is because water vapor during heat sterilization and water vapor in the packaged contents due to heating permeate the plastic film and come into direct contact with the ink film. Therefore, if the ink film lacks water resistance, the adhesive force between the layers is lowered as well as the adhesiveness, resulting in a peeling phenomenon and poor appearance.

However, when a flocculating pretreatment liquid as described in Patent Document 1 is used, the polyvalent metal salt contained in the pretreatment liquid as a flocculating agent is highly soluble in water, so the ink film is less resistant to water. Inferior to this, the adhesive force is lowered and the appearance is poor when the soft packaging material is thermally sterilized.

As described above, especially in high-speed printing such as the one-pass printer method, it is possible to obtain printed matter with excellent image quality without color mixture bleeding and color unevenness, and adhesive strength during heat sterilization treatment of flexible packaging materials. A water-based inkjet ink set containing a flocculating pretreatment liquid with good appearance has not existed until now.

JP 2005-074655 A JP 2006-281568 A JP-A-07-257015 JP-A-07-257016 JP-A-2006-334911

The present invention has been made to solve the above problems, and in one-pass printer type inkjet printing, it is particularly excellent in drying and adhesion to non-permeable substrates such as coated paper and film substrates, and To provide an aggregating pretreatment liquid capable of obtaining an excellent image quality free from color mixture bleeding and color unevenness, as well as a printed matter excellent in water resistance and scratch resistance. It is another object of the present invention to provide a pretreatment liquid, a water-based inkjet ink set, and a printed material which are excellent in adhesive strength and appearance even after thermal sterilization of soft packaging materials.

That is, the present invention provides a pretreatment liquid for inkjet printing of a one-pass printer system,
containing resin fine particles (A), a flocculant (B), and water,
The flocculant (B) contains a water-soluble cationic resin (C) having a structural unit derived from a vinyl monomer (c1) having a cationic group,
It relates to a pretreatment liquid that satisfies the following (1) and (2) in an elution curve when the entire water-soluble cation resin (C) is measured by gel permeation chromatography.
(1) Having a high molecular weight component (H) having a maximum value at a molecular weight of 5000 or more with a molecular weight of 5000 as a boundary and a low molecular weight component (L) having a maximum value at a molecular weight of 100 to 5000, and having the molecular weight of 5000 as a boundary , the area ratio of the elution curves of the high molecular weight component (H) and the low molecular weight component (L) is H/L = 75/25 to 97/3; (2) the weight average molecular weight is 50,000 to 200; , 000

（一般式（１）中、Ｒ^１は水素原子またはメチル基を表し 、Ｚは酸素原子、－ＮＨ－、または、－Ｏ－ＣＨ_２－ＮＨ－Ｃ（＝Ｏ）Ｏ－を表す。Ｒ^２ 、Ｒ^３、Ｒ^４ は各々独立して、メチル基、エチル基、またはプロピル基を表し、同じであっても異なっていてもよい。Ｘ^－はハロゲン化物イオン、スルホン酸アニオン、アルキルスルホン酸アニオン、酢酸アニオン、またはアルキルカルボン酸アニオンを表す。ｎは２～６の整数を表す。） The present invention also relates to the above pretreatment liquid, wherein the vinyl monomer (c1) having a cationic group has a structure represented by the following general formula (1).
General formula (1)

(In general formula (1), R ¹ represents a hydrogen atom or a methyl group, Z represents an oxygen atom, -NH-, or -O-CH ₂ -NH-C(=O)O-. R ² , R ³ and R ⁴ each independently represent a methyl group, an ethyl group or a propyl group, which may be the same or different, and ^{X −} represents a halide ion, a sulfonate anion or an alkylsulfonate anion. , represents an acetate anion or an alkylcarboxylate anion. n represents an integer of 2 to 6.)

The present invention also relates to the above pretreatment liquid, wherein the content of the water-soluble cationic resin (C) is 60 to 200 parts by mass with respect to 100 parts by mass of the fine resin particles (A).

The present invention also relates to the above pretreatment liquid, wherein the resin fine particles (A) have a glass transition temperature of -50 to 50°C.

The present invention also relates to the above pretreatment liquid for inkjet printing on impermeable substrates.

The present invention also provides a water-based inkjet ink set comprising the pretreatment liquid and one or more types of water-based inkjet inks,
The present invention relates to a water-based inkjet ink set, wherein at least one of the water-based inkjet inks contains a pigment (P), a pigment dispersion resin (D), and water.

The present invention also provides a method for producing a printed matter, comprising printing the water-based inkjet ink set on a non-permeable substrate, comprising:
a step of printing a pretreatment liquid on the impermeable base material in an amount such that the film thickness after drying is 0.1 to 1.6 μm;
a step of printing a water-based inkjet ink on a portion of the impermeable substrate printed with the pretreatment liquid by one-pass inkjet printing;
and drying the impermeable substrate printed with the water-based inkjet ink.

According to the present invention, the water-soluble cationic resin (C) in the pretreatment liquid contains a predetermined amount of the high molecular weight component (H) and the low molecular weight component (L), so that it can It is a cohesive type that has excellent drying and adhesion to the material, and can obtain printed matter with excellent image quality, water resistance, and scratch resistance with no mixed color bleeding or color unevenness in one-pass printer type inkjet printing. It became possible to provide a pretreatment liquid. In addition, it has become possible to provide a pretreatment liquid, a water-based inkjet ink set, and a printed material that have good adhesion and appearance even after heat sterilization of soft packaging materials.

The water-based inkjet ink of the present invention will be described below with reference to preferred embodiments. Hereinafter, "aqueous inkjet ink" may be referred to as "aqueous ink" or "ink".

The pretreatment liquid of the present invention is for one-pass printer type inkjet printing.
In the present invention, “1-pass printer type inkjet printing (hereinafter sometimes referred to as “1-pass inkjet printing”)” refers to scanning the inkjet head only once with respect to the stationary substrate, or In this method, the base material is passed through the lower part of the inkjet head only once for printing. However, when the ink jet head is scanned, it is necessary to adjust the ejection timing in consideration of the movement of the ink jet head, which tends to cause deviation of the landing position. Therefore, when printing water-based ink, it is preferable to use a method in which the substrate is passed under a fixed inkjet head.

<Resin fine particles (A)>
The pretreatment liquid of the present invention contains fine resin particles (A). The “resin fine particles” in the present invention refer to those having a particle diameter of 5 to 1000 nm as measured by the method described below. In the present invention, particles having a particle size larger than 1000 nm are referred to as "resin particles" to distinguish them from fine resin particles.

The kind of resin fine particles (A) that can be used in the pretreatment liquid of the present invention is not particularly limited. From the viewpoint of adhesion to substrates, polyurethane resins, polyurea resins, polyurethane urea resins, poly(meth)acrylic resins, acrylic-modified polyurethane resins, styrene-(meth)acrylic resins, styrene-(anhydride) maleic acid resins, rosin-modified It preferably contains one or more selected from the group consisting of maleic acid resins, polyolefin resins, polyester resins, polyether resins, and polycarbonate resins. Polyurethane resins, polyurethane-polyurea resins, poly(meth)acrylic resins, acrylic-modified polyurethane resins, and polyolefin resins are preferred, and one or more selected from the group consisting of polyolefin resins is particularly preferred. In the present invention, "(meth)acryl" means acryl and/or methacryl, and "(anhydride) maleic acid" means maleic acid and/or maleic anhydride.

The pretreatment liquid of the present invention may contain only one type of the resin fine particles (A) exemplified above, or may contain two or more types in combination. , an acrylic-modified polyurethane resin, and a polyolefin resin. This is because by using a combination of fine resin particles with different properties and types, it is possible to achieve both the adhesion between the ink surface and the base material, blocking resistance, drying performance, and the storage stability of the pretreatment liquid. be. Among them, from the viewpoint of achieving both of the above properties, it is particularly preferable that the fine resin particles (A) contain two or more selected from the group consisting of polyurethane resins, polyurethane polyurea resins, and poly(meth)acrylic resins.

As the resin fine particles (A), those synthesized by a known synthesis method may be used, or commercially available products may be used. When selecting from commercially available products, for example, ADEKA BONDITATER HUX series (manufactured by ADEKA); Juliano series (manufactured by Arakawa Chemical Industries); Parasol series (manufactured by Ohara Palladium Chemical Co., Ltd.); Kasei Kogyo Co., Ltd.); Superflex series, Superflex E series (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.); WBR series (manufactured by Taisei Fine Chemical Co., Ltd.); Hydran series (manufactured by DIC Corporation); ); Superchron series, Auroren series (manufactured by Nippon Paper Industries); Nichigo Polyester series (manufactured by Nippon Synthetic Chemical Co., Ltd.); ); Pascor series (manufactured by Meisei Chemical Industry Co., Ltd.); Arrow Base series (manufactured by Unitika Ltd.); NeoCryl series and NeoRez series (manufactured by DSM Coating Resins).

The amount of the fine resin particles (A) contained in the pretreatment liquid of the present invention is preferably 1 to 40% by mass, more preferably 1 to 30% by mass in terms of solid content, relative to the total amount of the pretreatment liquid. More preferably, 3 to 20% by mass is particularly preferable. By setting the blending amount of the fine resin particles (A) within the above range, the storage stability of the pretreatment liquid is improved, and a printed matter with excellent adhesion of the ink surface to the substrate and excellent image quality can be obtained.

(Melting point of fine resin particles (A))
The melting point of the fine resin particles (A) is preferably 0 to 130°C. It is more preferably 15 to 105°C, and particularly preferably 30 to 90°C. When the melting point is 0° C. or higher, the storage stability of the pretreatment liquid is good, and when it is 130° C. or lower, the adhesiveness to the substrate is excellent. The melting point is a value measured using differential scanning calorimetry (DSC), and can be measured, for example, as follows. About 2 mg of a sample obtained by drying the resin is weighed in an aluminum sample container, and then the aluminum sample container is set in a holder in a DSC measuring device (for example, "DSC-60Plus" manufactured by Shimadzu Corporation). Then, the temperature of the endothermic peak read from the obtained DSC chart is taken as the melting point in the present invention. Indium is used for temperature calibration.

(Glass Transition Temperature of Resin Fine Particles (A)) From the viewpoint of excellent adhesion to the substrate, the glass transition temperature (Tg) of the resin fine particles (A) is preferably −50 to 50° C., and −40 to 40. °C is more preferred, and -30 to 35°C is particularly preferred. Similar to the melting point, the glass transition temperature can also be measured by differential scanning calorimetry (DSC). Specifically, from the DSC chart obtained by the above method, the intersection point of the baseline on the low temperature side and the tangent line at the inflection point of the baseline is obtained, and the temperature of the intersection point is taken as the glass transition temperature.

(Particle diameter of resin fine particles (A))
The particle diameter (D ₅₀ ) of the fine resin particles (A) is preferably 30 to 500 nm, more preferably 40 to 400 nm, particularly preferably 50 to 300 nm. When the thickness is 30 nm or more, the storage stability of the pretreatment liquid is good, and when it is 500 nm or less, a printed matter having excellent adhesion of the ink surface to the substrate can be obtained. In this specification, the particle diameter (D ₅₀ ) is measured by a dynamic light scattering method using a particle size distribution analyzer (for example, Microtrac UPAEX-150 manufactured by Microtrac Bell), based on volume. Cumulative 50% diameter value (median diameter).

<Flocculant (B)>
The pretreatment liquid of the present invention further contains a flocculant (B).
The flocculant (B) contains a water-soluble cationic resin (C) having a structural unit derived from a vinyl monomer (c1) having a cationic group.

The effect of the cationic component derived from the water-soluble cationic resin (C) to agglomerate the solid components in the water-based inkjet ink and/or the effect of causing thickening due to the interaction between the components having anionic groups makes the image Prints with excellent quality can be obtained.

[Water-soluble cationic resin (C)]
The water-soluble cation resin (C) used in the present invention satisfies the following (1) and (2) in the elution curve when the entire water-soluble cation resin (C) is measured by gel permeation chromatography. .
(1) Having a high molecular weight component (H) having a maximum value at a molecular weight of 5000 or more with a molecular weight of 5000 as a boundary and a low molecular weight component (L) having a maximum value at a molecular weight of 100 to 5000, and having the molecular weight of 5000 as a boundary , the area ratio of the elution curves of the high molecular weight component (H) and the low molecular weight component (L) is H/L = 75/25 to 97/3; (2) the weight average molecular weight is 50,000 to 200; , 000

In the present specification, the term "whole water-soluble cationic resin (C)" refers to the resin when the water-soluble cationic resin is included alone, and refers to a mixture of these resins when the water-soluble cationic resin is included. .

In the present invention, the structural unit derived from a vinyl monomer includes a structural unit in which a carbon-carbon double bond of a vinyl monomer can be formed as a result of a bond-forming reaction such as addition polymerization, and equivalents thereof. As a structural unit that the carbon-carbon double bond of a vinyl monomer can be generated as a result of a bond-forming reaction such as addition polymerization, the carbon-carbon double bond becomes a single bond as a result of a bond-forming reaction such as addition polymerization. contains different structural units. In addition, as long as the structural unit is a single bond, it may be a structural unit formed by a method other than polymerizing a vinyl monomer as a monomer, regardless of the synthesis method.

[Content ratio of water-soluble cationic resin (C)]
The content of the water-soluble cationic resin (C) in the pretreatment liquid is preferably 60 to 200 parts by mass, more preferably 80 to 160 parts by mass, and more preferably 100 to 100 parts by mass. 150 parts by mass is particularly preferred. By setting the blending amount of the water-soluble cationic resin (C) within the above range, it is possible to suppress bleeding and color mixture, obtain printed matter with excellent image quality, and obtain a pretreatment liquid with excellent storage stability.

（一般式（１）中、Ｒ^１は水素原子またはメチル基を表し 、Ｚは酸素原子、－ＮＨ－、または、－Ｏ－ＣＨ_２－ＮＨ－Ｃ（＝Ｏ）Ｏ－を表す。Ｒ^２ 、Ｒ^３、Ｒ^４ は各々独立して、メチル基、エチル基、プロピル基を表し、同じであっても異なっていてもよい。Ｘ^－はハロゲン化物イオン、スルホン酸アニオン、アルキルスルホン酸アニオン、酢酸アニオン、またはアルキルカルボン酸アニオンを表す。ｎは２～６の整数を表す。） In addition, from the viewpoint of suppressing color mixture bleeding on impermeable substrates and giving printed matter with excellent appearance even after hot water sterilization, the vinyl monomer (c1) having a cationic group is represented by the following general formula (1) is preferably a structure represented by
General formula (1)

(In general formula (1), R ¹ represents a hydrogen atom or a methyl group, Z represents an oxygen atom, -NH-, or -O-CH ₂ -NH-C(=O)O-. R ² , R ³ and R ⁴ each independently represent a methyl group, an ethyl group or a propyl group, which may be the same or different, ^{X −} represents a halide ion, a sulfonate anion, an alkylsulfonate anion, represents an acetate anion or an alkylcarboxylate anion, where n represents an integer of 2 to 6.)

In general formula (1), R ¹ represents a hydrogen atom or a methyl group.

In general formula (1), Z represents an oxygen atom, -NH-, or -O-CH ₂ -NH-C(=O)O-. From the viewpoint of ease of synthesis, it is preferably an oxygen atom or -NH-.

In general formula (1), R ² , R ³ and R ⁴ each independently represent a methyl group, an ethyl group or a propyl group and may be the same or different. From the viewpoint of solubility in inkjet ink, at least one of R ² , R ³ and R ⁴ is preferably a methyl group.

In general formula (1), X 1 ⁻ represents a halide ion, sulfonate anion, alkylsulfonate anion, acetate anion, or alkylcarboxylate anion.

In general formula (1), n represents an integer of 2-6. From the viewpoint of ease of synthesis, n is preferably 2-5, more preferably 3-4.

Examples of the vinyl monomer (c1) containing a cationic group include (meth)acryloyloxyethyltrimethylammonium chloride, (meth)acryloyloxyethyltriethylammonium chloride, (meth)acryloyloxyethyldimethylbenzylammonium chloride, (meth)acryloyloxyethyltrimethylammonium chloride, (meth) ) Acryloyloxyethylmethylmorpholino ammonium chloride, 2-hydroxy-3-(meth)acryloyloxypropyltrimethylammonium chloride and other alkyl (meth)acrylate quaternary ammonium salts, (meth)acryloylaminopropyltrimethylammonium chloride, (meth ) Alkyl(meth)acryloylamide-based quaternary ammonium salts such as acryloylaminoethyltriethylammonium chloride, (meth)acryloylaminoethyldimethylbenzylammonium chloride, dimethyldiallylammonium methylsulfate and trimethylvinylphenylammonium chloride.
These cationic group-containing vinyl monomers (c1) can be used singly or in combination.

(vinyl monomer (c2) having an amino group)
Further, in the present invention, the water-soluble cationic resin (C) contains a structural unit derived from a vinyl monomer (c2) having an amino group in addition to the structural unit derived from the vinyl monomer (c1) having a cationic group. preferably included. As a result, it is possible not only to exhibit cohesiveness with water-based inkjet ink, but also to control the wettability, and to obtain a printed matter having excellent image quality without color unevenness.

The water-soluble cationic resin (C) used in the present invention is, for example, a cationic group-containing vinyl monomer (c1) and, if necessary, an amino group-containing vinyl monomer (c2), a vinyl It can be obtained by polymerization.

In addition to polymerization using the vinyl monomer containing the above cationic group, for example, an ethylenically unsaturated monomer (c2) having an amino group is copolymerized as a monomer component to have an amino group. After the acrylic resin is obtained, it is allowed to react with an onium chloride agent and subjected to ammonium chloride to obtain a resin having a structural unit derived from the cationic vinyl monomer (c1).

Examples of onium chloride agents include alkyl sulfates such as dimethyl sulfate, diethyl sulfate, and dipropyl sulfate; sulfonate esters such as methyl p-toluenesulfonate and methyl benzenesulfonate; methyl chloride, ethyl chloride, propyl chloride; Examples include alkyl chlorides such as octyl chloride, alkyl bromides such as methyl bromide, ethyl bromide, propyl bromide, or octyl bromide, or benzyl chloride or benzyl bromide.

Examples of the vinyl monomer (c2) having an amino group include dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dipropylaminoethyl (meth)acrylate, diisopropylaminoethyl (meth)acrylate, dibutylamino Ethyl (meth)acrylate, diisobutylaminoethyl (meth)acrylate, di-t-butylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylamide, diethylaminopropyl (meth)acrylamide, dipropylaminopropyl (meth)acrylamide, diisopropyl (Meth)acrylic acid esters or (meth)acrylamides having a dialkylamino group such as aminopropyl (meth)acrylamide, dibutylaminopropyl (meth)acrylamide, diisobutylaminopropyl (meth)acrylamide, di-t-butylaminopropyl (meth)acrylamide styrenes having a dialkylamino group such as dimethylaminostyrene and dimethylaminomethylstyrene; diallylamine compounds such as diallylmethylamine and diallylamine; amino compounds such as N-vinylpyrrolidine, N-vinylpyrrolidone and N-vinylcarbazole A group-containing aromatic vinyl-based monomer can be mentioned.
These amino group-containing vinyl monomers (c2) can be used singly or in combination.

By using the vinyl monomer (c2) containing these amino groups, the cationic component derived from the flocculant (B) acts to flocculate the solid components in the water-based inkjet ink and/or the component having an anionic group. Prints with excellent image quality can be obtained from the effect of causing thickening due to interaction between them.

Further, the vinyl monomer (c2) containing an amino group can be obtained by modifying the isocyanate group of the monomer containing 2-methacryloyloxyethyl isocyanate with a compound that reacts with the isocyanate group.
Examples of compounds that react with isocyanate groups include 2-dimethylamino-1-ethanol, 3-dimethylamino-1-propanol, methylaminopropanol, 4-dimethylamino-1-butanol, 1-methyl-4-piperidinemethanol, 5-diethylamino-1-pentanol, 6-dimethylamino-1-hexanol.

(Other vinyl monomer (c3))
In another embodiment, the water-soluble cationic resin (C) used in the present invention includes, for example, a vinyl monomer (c1) containing a cationic group and, optionally, a vinyl monomer containing an amino group ( It is obtained by vinyl-polymerizing c2) and a vinyl monomer (c3) other than (c1) or (c2).

As the vinyl monomer (c3) other than (c1) or (c2),
For example, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, Styrenic monomers such as pn-hexylstyrene, p-methoxystyrene, p-phenylstyrene;
methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2- Ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, myristyl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, behenyl (meth)acrylate, tetratria Alkyl group-containing (meth)acrylic monomers such as kontanoyl (meth)acrylate and hexatriacontanoyl (meth)acrylate;
(Poly) ethylene glycol mono (meth) acrylate, (poly) propylene glycol mono (meth) acrylate, (poly) butylene glycol mono (meth) acrylate, (poly) (ethylene glycol-propylene glycol) mono (meth) acrylate, ( Poly)ethylene glycol mono(meth)acrylate monomethyl ether, (poly)ethylene glycol mono(meth)acrylate monobutyl ether, (poly)ethylene glycol mono(meth)acrylate monooctyl ether, (poly)ethylene glycol mono(meth)acrylate mono Alkylene oxide chains such as benzyl ether, (poly)ethylene glycol mono(meth)acrylate monophenyl ether, (poly)ethylene glycol mono(meth)acrylate monohexadecyl ether, (poly)ethylene glycol mono(meth)acrylate monooctadecyl ether containing (meth)acrylic monomer;
aromatic ring-containing (meth)acrylic monomers such as phenyl (meth)acrylate, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate;
Polyfunctionality such as diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, etc. (meth) acrylic monomer;
trimethylsilyl (meth)acrylate, triethylsilyl (meth)acrylate, tri-n-propylsilyl (meth)acrylate, tri-n-butylsilyl (meth)acrylate, tri-n-amylsilyl (meth)acrylate, tri-n-hexylsilyl (Meth)acrylate, tri-n-octylsilyl (meth)acrylate, tri-n-dodecylsilyl (meth)acrylate, triphenylsilyl (meth)acrylate, tri-p-methylphenylsilyl (meth)acrylate, tribenzylsilyl (Meth) acrylate, triisopropylsilyl (meth) acrylate, triisobutylsilyl (meth) acrylate, tri (s-butyl) silyl (meth) acrylate, tri (2-methylisopropyl) silyl (meth) acrylate, tri (t- Butyl)silyl (meth)acrylate, ethyldimethylsilyl (meth)acrylate, n-butyldimethylsilyl (meth)acrylate, diisopropyl (n-butyl)silyl (meth)acrylate, n-octyldi(n-butyl)silyl (meth)acrylate acrylates, diisopropylstearylsilyl (meth)acrylate, dicyclohexylphenylsilyl (meth)acrylate, t-butyldiphenylsilyl (meth)acrylate, lauryldiphenylsilyl (meth)acrylate, triisopropylsilylmethyl maleate, triisopropylsilyl amyl malate, tri(n-butyl)silyl(n-butyl)malate, (t-butyldiphenylsilyl)(methyl)malate, (t-butyldiphenylsilyl)(n-butyl)malate, (triisopropylsilyl)(methyl)fumarate, (triisopropylsilyl)(amyl)fumarate, (tri(n-butylsilyl))(n-butyl)fumarate, (t-butyldiphenylsilyl)(methyl)fumarate, (t-butyldiphenylsilyl)(n-butyl)fumarate , Silaplane FM-0711 (manufactured by JNC), Silaplane FM-0721 (manufactured by JNC), Silaplane FM-0725 (manufactured by JNC), Silaplane TM-0701 (manufactured by JNC), Silaplane TM-0701T (manufactured by JNC), X-22-174ASX (manufactured by Shin-Etsu Chemical Co., Ltd.), X-22-174BX (manufactured by Shin-Etsu Chemical Co., Ltd.), KF-2012 (manufactured by Shin-Etsu Chemical Co., Ltd.), X-22-2426 (manufactured by Shin-Etsu Chemical Co., Ltd.) Chemical Industry Co., Ltd.), X-22-2404 (Shin-Etsu Chemical Co., Ltd.) and other organosilyl group-containing monomers;
Viscoat 3F (2,2,2-trifluoroethyl acrylate, manufactured by Osaka Organic Chemical Industry Co., Ltd.), Light Ester M-3F (2,2,2-trifluoroethyl, manufactured by Kyoeisha Chemical Co., Ltd.), Viscoat 4F (acrylic acid 2,2,3,3-tetrafluoropropyl, manufactured by Osaka Organic Chemical Industry Co., Ltd.), Viscoat 8F (1H,1H,5H-octafluoropentyl acrylate, manufactured by Osaka Organic Chemical Industry Co., Ltd.), Viscoat 8FM (methacrylic acid 1H , 1H,5H-octafluoropentyl, manufactured by Osaka Organic Chemical Industry Co., Ltd.), Viscoat 13F (1H,1H,2H,2H-tridecafluorooctyl acrylate, manufactured by Osaka Organic Chemical Industry Co., Ltd.), methacrylic acid 2,2,3 , 3,3-pentafluoropropyl (manufactured by Tokyo Chemical Industry Co., Ltd.), 1,1,1,3,3,3-hexafluoroisopropyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 1H,1H-perfluoro- methacrylate N-decyl (1H,1H-nonadecafluorodecyl methacrylate, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 2-(perfluorodecyl)ethyl methacrylate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), pentafluorobenzyl methacrylate ( Apollo Scientific Co., Ltd.) and other fluorine atom-containing (meth)acrylic monomers;
is mentioned.

As the other vinyl monomer (c3), it is preferable to use the above organosilyl group-containing monomer and/or fluorine atom-containing (meth)acrylic monomer. By using these monomers, the surface free energy of the water-soluble cationic resin (C) can be lowered. As a result, the water-soluble cationic resin (C) is oriented on the outermost surface of the coating film on the impermeable substrate, and the cationic groups in the water-soluble cationic resin (C) are oriented on the outermost surface, so that water-based inkjet The ink can be efficiently agglomerated and the image quality can be improved.

(Amine value of water-soluble cationic resin (C))
When the water-soluble cationic resin (C) contains a structural unit derived from a vinyl monomer (c1) having a cationic group and a structural unit derived from a vinyl monomer (c2) having an amino group, a preferred amine value is 50 to 300 mgKOH/g, preferably 80 to 250 mgKOH/g, more preferably 100 to 200 mgKOH/g. When the amine value is 50 mgKOH/g or more, the wettability of the water-soluble ink is improved, resulting in a good printed image. On the other hand, when it is 300 mgKOH/g or less, the adhesion to the substrate is improved.

(Weight average molecular weight of water-soluble cationic resin (C))
The weight average molecular weight (Mw) of the water-soluble cationic resin (C) can be measured by a conventional method. In the present invention, a gel permeation chromatography (manufactured by Tosoh Corporation, HLC-8320GPC) equipped with a TSKgel column (manufactured by Tosoh Corporation) and an RI detector is used, and a 0.1 mol/l sodium nitrate aqueous solution is used as a developing solvent. Measured using a standard reagent and converted to polyethylene oxide.

The water-soluble cationic resin (C) has an overall weight average molecular weight of 50,000 to 200,000, preferably 75,000 to 150,000, more preferably 90,000 to 150,000. preferable. When the weight-average molecular weight is 50,000 or more, color mixing and bleeding of ink are suppressed, resulting in good print quality, sufficient adhesion after lamination, and suppression of delamination after heat sterilization. can do. If it is 200,000 or less, it has excellent solubility and diffusibility in water, and when it comes into contact with droplets of water-based inkjet ink, it mixes quickly, causing the droplets to thicken and aggregate, resulting in wetting on the substrate. It is possible to suppress spreading and obtain a printed matter excellent in image quality.

(High molecular weight component (H) and low molecular weight component (L) of water-soluble cationic resin (C))
In the present invention, the water-soluble cation resin (C) is composed of a high molecular weight component (H) having a maximum molecular weight of 5000 or more and a molecular weight of 100 with a molecular weight of 5000 as a boundary in the elution curve in the gel permeation chromatography measurement. It is necessary to have a low molecular weight component (L) with a maximum at ~5000.

By including the high molecular weight component (H) and the low molecular weight component (L) in the water-soluble cationic resin (C), the printability is further improved, and the water resistance, scratch resistance, and adhesive strength after lamination are sufficiently improved. can be ensured, and the peeling phenomenon after heat sterilization can be suppressed. Here, the low-molecular-weight component (L) has a different composition from conventionally known wetting agents (surface conditioners and surfactants), etc., and has a cationic substituent with a quaternary ammonium salt structure, so it aggregates during high-speed printing. It is thought that the performance of these properties contributes to the formation of good printed images. In addition, by setting the area ratio of the elution curve in GPC between the high molecular weight component (H) and the low molecular weight component (L) to 75/25 to 97/3, the peeling phenomenon after heat sterilization is suppressed and the printed matter Effective in developing water resistance and scratch resistance. The area ratio is more preferably 85/15 to 95/5.

Such a water-soluble cationic resin (C) can be obtained by a known method such as dropwise polymerization of the vinyl polymer described above. The component of each molecular weight may be a water-soluble cationic resin (C), a vinyl monomer having a cationic group (c1), a vinyl monomer containing an amino group (c2 ), or a vinyl monomer (c3) other than (c1) or (c2).

Also, the low molecular weight component (L) having a maximum molecular weight of 100 to 5000 may be a compound having a structure represented by general formula (1).

The flocculant (B) preferably has low hygroscopicity. When the coagulant (B') with low hygroscopicity is used, not only can a printed matter with excellent adhesion between the ink surface and the substrate and scratch resistance be obtained, but the printed matter can be stored in a high-humidity environment or for a long period of time. This is because it does not absorb moisture in the atmosphere even in such a case, and can maintain excellent quality over a long period of time.

In the present invention, the term "flocculant with low hygroscopicity" specifically refers to a coagulant having a hygroscopic weight increase rate of 80% by mass or less as measured by the method described below. First, the flocculant is stored for 24 hours in an environment with a temperature of 100° C. and a relative humidity of 75% RH or less. If the coagulant is available only in the form of an aqueous solution, such as a commercially available product, the water is removed by volatilization in advance, and then stored under an environment of 100° C. and 75% RH or less. After storing in an environment of 100°C and 75% RH or less, measure the weight of the flocculant (W1 (g)), and then store it in an environment of 40°C and 80% RH for 24 hours. . After storage in an environment of 40° C. and 80% RH, the weight is measured again (referred to as W2 (g)), and the hygroscopic weight increase rate is calculated by the following formula (1).

Formula (1): Moisture absorption weight increase rate (% by mass) = 100 x {(W2-W1)/W1}

From the standpoint of obtaining printed matter with excellent image quality and adhesion between the ink surface and the substrate even when the substrate to which the pretreatment liquid of the present invention has been applied is stored for a long period of time in a high-humidity environment, The moisture absorption weight increase rate of the flocculant (B′) is 80% by mass or less, more preferably 40% by mass or less.

[Metal salt]
In the pretreatment liquid of the present invention, a water-soluble cationic resin (C) and a metal salt may be used in combination as the flocculant (B).
When combining a metal salt as the aggregating agent (B), any material can be used as long as it can aggregate and thicken the water-based inkjet ink. In addition, it is preferable to select one having excellent solubility in the pretreatment liquid and diffusibility in the liquid. In addition, you may use a metal salt in combination of 2 or more types.

The type of metal salt is not particularly limited as long as it is composed of a metal ion and an anion that binds to the metal ion. Among them, it is preferable that the metal salt contains a polyvalent metal salt from the viewpoint of suppressing bleeding and color mixing and obtaining a clear image by instantaneously interacting with the pigment. Although the details are unknown, it is more preferable that the polyvalent metal ions constituting the polyvalent metal salt are trivalent cations, particularly aluminum ions, in order to obtain a pretreatment liquid with excellent storage stability. Metal salts include inorganic metal salts and organic metal salts.

Specific examples of inorganic metal salts include aluminum chloride, polyaluminum chloride (PAC), calcium chloride, magnesium chloride, aluminum chloride, calcium bromide, magnesium bromide, aluminum nitrate, calcium nitrate, magnesium nitrate, aluminum sulfate, magnesium sulfate, Examples include, but are not limited to, calcium carbonate and magnesium carbonate. Among these inorganic metal salts, it is preferable to select aluminum sulfate and/or aluminum nitrate from the viewpoint of hygroscopicity and aggregation/thickening effect of water-based inkjet ink.

Specific examples of organic metal salts include, but are not limited to, aluminum salts, calcium salts, magnesium salts, nickel salts, and zinc salts of organic acids such as pantothenic acid, propionic acid, ascorbic acid, acetic acid, and lactic acid. not something. Among these metal salts of organic acids, it is preferable to select aluminum salts or calcium salts of lactic acid and/or acetic acid from the viewpoint of hygroscopicity and aggregation/thickening effects of water-based inkjet inks.

The content of the metal salt in the pretreatment liquid of the present invention is preferably 0.25 to 8.0% by mass, more preferably 0.75 to 6.5% by mass, as metal ions, relative to the total amount of the pretreatment liquid. %, and particularly preferably 0.75 to 3% by mass. By setting the content of metal ions within the above range, the wettability of the pretreatment liquid to the substrate can be ensured. In addition, it is also suitable because it can improve the drying property of printed matter.

<Water>
The pretreatment liquid of the present invention further contains water. And it is preferable to contain water as a main component. In the present specification, "containing water as a main component" means that the amount of water blended is the largest among all the constituent components.

The content of water contained in the pretreatment liquid of the present invention is preferably in the range of 30 to 95% by mass, more preferably 40 to 90% by mass, more preferably 50 to 85% by mass, relative to the total amount of the pretreatment liquid. % is particularly preferred. Since water enhances the mutual solubility of various materials such as the resin fine particles (A), the coagulant (B), and surfactants, water is an indispensable material for improving the storage stability of the pretreatment liquid.

<Organic solvent>
The pretreatment liquid of the present invention may further contain an organic solvent. By using an organic solvent together, the solubility of the flocculant (B) and the drying property and wettability of the pretreatment liquid can be adjusted to be suitable. Only one type of organic solvent may be used, or two or more types may be used in combination.

Although the organic solvent to be used is not particularly limited, it preferably contains a water-soluble organic solvent. In the present invention, the term "water-soluble organic solvent" refers to a solvent that is liquid at 25°C and has a solubility in water at 25°C of 1% by mass or more.

Furthermore, the organic solvent used in the pretreatment liquid of the present invention has good affinity with the resin fine particles (A) and the coagulant (B), and from the viewpoint of improving the storage stability of the pretreatment liquid, It is more preferable to use a water-soluble organic solvent containing one or more hydroxyl groups in . From the viewpoint of improvement, it is particularly preferable to select a water-soluble organic solvent having a boiling point of 75 to 210° C. under 1 atm as the water-soluble organic solvent containing one or more hydroxyl groups in the molecular structure. In this specification, the boiling point under 1 atm is a value measured by a known method such as differential thermal analysis (DTA) or differential scanning calorimetry (DSC).

Water-soluble organic solvents containing one or more hydroxyl groups in the molecular structure include, for example, monohydric alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol; ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,5-pentane Diol, 1,2-hexanediol, 1,6-hexanediol, 1,2-heptanediol, 2,2-dimethyl-1,3-propanediol, 2-methyl-1,3-propanediol, 2-ethyl -2-methyl-1,3-propanediol, 3-methyl-1,3-butanediol, 3-methyl-1,5-pentanediol, 2-methyl-2-propyl-1,3-propanediol, 2 -methylpentane-2,4-diol, 2-ethyl-1,3-hexanediol, 1,2-octanediol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol #200, polyethylene glycol #400 , dipropylene glycol, tripropylene glycol, dibutylene glycol, dihydric alcohols (glycols); ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol mono Butyl ether, diethylene glycol monopentyl ether, diethylene glycol monohexyl ether, 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 monobutyl ether, dipropylene glycol monopropyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, 1,2-butylene glycol monomethyl ether, 1,3-butylene glycol monomethyl ether, and other glycol monoalkyl ethers. ethers; chain polyol compounds such as glycerin, trimethylolpropane, 1,2,4-butanetriol, 1,2,6-hexanetriol, diglycerin, and polyglycerin;

In addition to the above examples, the pretreatment liquid of the present invention includes diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol butyl methyl ether, diethylene glycol diethyl ether, triethylene glycol dimethyl ether, triethylene glycol methyl ethyl ether, triethylene glycol methyl ethyl ether, and triethylene glycol dimethyl ether. Glycol dialkyl ethers such as ethylene glycol butyl methyl ether, triethylene glycol diethyl ether, tetraethylene glycol dimethyl ether, tetraethylene glycol methyl ethyl ether, tetraethylene glycol butyl methyl ether, tetraethylene glycol diethyl ether; 2-pyrrolidone, N-methyl pyrrolidone, N-ethylpyrrolidone, ε-caprolactam, 3-methyl-2-oxazolidinone, 3-ethyl-2-oxazolidinone, N,N-dimethyl-β-methoxypropionamide, N,N-dimethyl-β-ethoxypropionamide , N,N-dimethyl-β-butoxypropionamide, N,N-dimethyl-β-pentoxypropionamide, N,N-dimethyl-β-hexoxypropionamide, N,N-dimethyl-β-heptoxypropionamide Amide, N,N-dimethyl-β-2-ethylhexoxypropionamide, N,N-dimethyl-β-octoxypropionamide, N,N-diethyl-β-butoxypropionamide, N,N-diethyl-β -Nitrogen-containing solvents such as pentoxypropionamide, N,N-diethyl-β-hexoxypropionamide, N,N-diethyl-β-heptoxypropionamide, and N,N-diethyl-β-octoxypropionamide heterocyclic compounds such as γ-butyrolactone, γ-valerolactone, δ-valerolactone, ε-caprolactone, and the like can be used.

The total amount of the organic solvent contained in the pretreatment liquid of the present invention is preferably 1 to 50% by mass, more preferably 2 to 40% by mass, more preferably 3 to 50% by mass, based on the total amount of the pretreatment liquid. 30% by mass is particularly preferred. By keeping the blending amount of the organic solvent within the above range, it is possible to obtain a pretreatment liquid in which both the solubility of the resin fine particles (A) and the coagulant (B) and the wettability with respect to the substrate are compatible. Stable printing is possible over a long period of time without causing printing defects regardless of the printing method of the treatment liquid.

When a water-soluble organic solvent containing one or more hydroxyl groups is used as the organic solvent, the amount is preferably 35 to 100% by mass, more preferably 50 to 100% by mass, based on the total amount of the organic solvent. is more preferable, and 65 to 100% by mass is particularly preferable. This is because the effect of the water-soluble organic solvent containing one or more hydroxyl groups is favorably exhibited by setting the blending amount within the above range.

Further, in the pretreatment liquid of the present invention, the content of the organic solvent having a boiling point of 240° C. or higher under 1 atmosphere is preferably less than 10% by mass with respect to the total amount of the pretreatment liquid (0% by mass may be acceptable). ). By not containing an organic solvent with a boiling point of 240° C. or higher, or by setting the blending amount within the above range even if it contains an organic solvent, a printed material with excellent image quality can be obtained, and the pretreatment liquid has sufficient drying properties. becomes.

Furthermore, for the same reason as above, the content of the organic solvent having a boiling point of 240° C. or higher at 1 atmosphere is less than 10% by mass with respect to the total amount of the pretreatment liquid, and the boiling point at 1 atmosphere The content of the organic solvent having a temperature of 220° C. or higher is preferably less than 15% by mass, more preferably less than 10% by mass, relative to the total amount of the pretreatment liquid.

<Surfactant>
The pretreatment liquid of the present invention may contain a surfactant. Surfactants include types such as siloxane-based, acrylic, fluorine-based, acetylene diol-based, and polyoxyalkylene alkyl ether-based surfactants. They may be used together.

By imparting suitable wettability on the substrate, a uniform pretreatment liquid layer can be formed, and from the viewpoint of being able to obtain printed matter with excellent image quality and adhesion between the ink surface and the substrate, the above-mentioned Among them, acetylene diol-based surfactants and/or polyoxyalkylene alkyl ether-based surfactants are preferably used.

Surfactants used in the pretreatment liquid of the present invention can be synthesized by known methods or commercially available products. When the surfactant is selected from commercial products, for example, Surfynol 61, 104E, 104H, 104A, 104BC, 104DPM, 104PA, 104PG-50, 420, 440, 465, 485, SE, SE- F, Dynol 604, 607 (manufactured by Air Products), Olphine E1004, E1010, E1020, PD-001, PD-002W, PD-004, PD-005, EXP. 4001, EXP. 4200, EXP. 4123, EXP. 4300 (manufactured by Nissin Chemical Industry Co., Ltd.), and as polyoxyalkylene alkyl ether surfactants, Emulgen series (manufactured by Kao Corporation), Emalmin series, Sannonic series, Sedran series, Naroacty series (Sanyo Chemical Industry Co., Ltd.) company), Pegnol series (manufactured by Toho Chemical Industry Co., Ltd.), Nonion series, Unilube series, and Unisafe series (manufactured by NOF Corporation). The above surfactants may be used alone, or two or more of them may be used in combination.

When the pretreatment liquid of the present invention contains a surfactant, the compounding amount thereof is 0.01 to 10% by mass based on the total amount of the pretreatment liquid from the viewpoint of forming a uniform pretreatment liquid layer on the substrate. 0.05 to 5% by mass is more preferable. Particularly preferably, it is 0.1 to 3% by mass.

<Surface conditioner>
The pretreatment liquid of the present invention preferably contains a surface conditioner for the purpose of improving the wettability of the substrate and preventing repelling. As used herein, the term "surface control agent" means a substance that has a hydrophilic site and a hydrophobic site in its molecular structure and that can adjust the surface tension of the ink composition when added.

Examples of surface conditioners that can be contained in the pretreatment liquid of the present invention include anionic surface conditioners such as dialkylsulfosuccinates, alkylnaphthalenesulfonates, and fatty acid salts, polyoxyethylene alkyl ethers, polyoxyethylene alkyl nonionic surface conditioners such as allyl ethers, acetylene glycols, and polyoxyethylene/polyoxypropylene block copolymers; cationic surface conditioners such as alkylamine salts and quaternary ammonium salts; silicon-based surface conditioners; Fluorine-based surface conditioners can be mentioned.

In particular, silicon-based surface conditioners and acrylic-based surface conditioners are preferred, and commercially available products such as BYK-Chemie, Evonik, and Dow Corning Toray can be used. These surface conditioners can be used alone or in combination of two or more. Furthermore, in the case of a silicone-based surface conditioner, it is preferably a polyether-modified silicone oil and has an HLB of 7.6 to 12.
The content of the surface conditioner in the pretreatment liquid of the present invention can be appropriately selected depending on the purpose of use, but is preferably 0.01 to 1% by mass in the pretreatment liquid, for example.

Specific examples of the surface conditioner include BYK-300, BYK-302, BYK-306, BYK-307, BYK-310, BYK-313, BYK-315N, BYK-320, BYK-322, BYK-323, BYK-325, BYK-326, BYK-330, BYK-331, BYK-333, BYK-342, BYK-345, BYK-346, BYK-347, BYK-348, BYK-349, BYK-350, BYK- 354, BYK-355, BYK-356, BYK-358N, BYK-361N, BYK-370, BYK-375, BYK-377, BYK-378, BYK-381, BYK-392, BYK-394, BYK-399, BYK-3440, BYK-3441, BYK-3455, BYK-3550, BYK-3560, BYK-3565, BYK-3760, BYK-DYNWET 800N, BYK-SILCLEAN 3700, BYK-SILCLEAN 3701, BYK-SILCLEAN 372 0, BYK- UV3500, BYK-UV3505, BYK-UV3510, BYK-UV3530, BYK-UV3535, BYK-UV3570, BYK-UV3575, BYK-UV3576 (manufactured by BYK-Chemie Japan),
TEGO Flow 300, TEGO Flow 370, TEGO Flow 425, TEGO Flow ATF 2, TEGO Flow ZFS 460, TEGO Glide 100, TEGO Glide 110, TEGO Glide 130, TEGO Glide 406, TEGO Glide 410, TEGO Glide 411, TEGO Glide 415, TEGO Glide 432, TEGO Glide 435, TEGO Glide 440, TEGO Glide 450, TEGO Glide 482, TEGO Glide A 115, TEGO Glide B 1484, TEGO Glide ZG 400 (manufactured by Evonik Japan), 5 01W ADDITIVE, FZ-2104, FZ-2110 , FZ-2123, FZ-2164, FZ-2191, FZ-2203, FZ-2215, FZ-2222, FZ-5609, L-7001, L-7002, L-7604, OFX-0193, OFX-0309 FLUID, OFX-5211 FLUID, SF 8410 FLUID, SH3771, SH 3746 FLUID, SH 8400 FLUID, SH 8700 FLUID, Y-7006 (manufactured by Dow Corning Toray Co., Ltd.),
KF-351A, KF-352A, KF-353, KF-354L, KF-355A, KF-615A, KF-640, KF-642, KF-643, KF-644, KF-945, KF-6004, KF- 6011, KF-6012, KF-6015, KF-6017, KF-6020, KF-6204, X-22-2516, X-22-4515 (manufactured by Shin-Etsu Chemical Co., Ltd.).

Among these, in terms of structure and HLB, BYK-35651, ADDITIVE, FZ-2104, FZ-2123, FZ-2215, L-7002, OFX-0309 FLUID, OFX-5211 FLUID, SH 8400 FLUID, KF-351A , KF-353, KF-355A, KF-615A, KF-642, KF-644, KF-6004, KF-6011, KF-6204 are preferred.

<pH adjuster>
The pretreatment liquid of the present invention can contain a pH adjuster. By using a pH adjuster, damage to the components used in the coating equipment can be suppressed, and pH fluctuations over time can be suppressed to maintain the performance of the pretreatment solution over the long term and maintain storage stability.・It can be improved. Materials that can be used as the pH adjuster are not limited, and one type may be used alone, or two or more types may be used in combination. Specifically, when the pretreatment liquid is basified, alkanolamine such as dimethylethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine; aqueous ammonia; lithium hydroxide, sodium hydroxide, potassium hydroxide. and alkali metal hydroxides such as lithium carbonate, sodium carbonate, sodium hydrogencarbonate, and potassium carbonate. In addition, when acidifying the pretreatment liquid, hydrochloric acid, sulfuric acid, acetic acid, citric acid, maleic acid, maleic anhydride, succinic acid, tartaric acid, malic acid, phosphoric acid, boric acid, fumaric acid, malonic acid, ascorbic acid Acids, glutamic acid and the like can be used.

The blending amount of the pH adjuster is preferably 0.01 to 5% by mass, more preferably 0.1 to 4.5% by mass, based on the total amount of the pretreatment liquid. By keeping the blending amount of the pH adjuster within the above range, pH changes due to external stimuli such as dissolution of carbon dioxide in the atmosphere are less likely to occur, and the effects of the resin fine particles (A) and the coagulant (B) are enhanced. Does not inhibit expression.

<Colorant>
In a preferred embodiment, the pretreatment liquid of the present invention is substantially free of coloring agents such as pigments and dyes. By using a pretreatment liquid that does not contain a coloring agent and is substantially transparent, it is possible to obtain a printed matter that takes advantage of the color and transparency that are unique to the base material. In the present invention, "substantially free" means that the intentional addition of the material is not permitted to the extent that it interferes with the manifestation of the effects of the present embodiment. It does not exclude unintended contamination as a product. Specifically, the material should not be contained in an amount of 2.0% by mass or more, preferably 1.0% by mass or more, more preferably 0.5% by mass or more, based on the total amount of the pretreatment liquid. It should not be contained, and particularly preferably should not be contained in an amount of 0.1% by mass or more.

On the other hand, in another preferred embodiment, the pretreatment liquid of the present invention contains a white pigment as a coloring agent. By using a white pretreatment liquid on a colored and/or transparent base material, a printed matter with excellent sharpness and visibility can be obtained. When the pretreatment liquid of the present invention contains a white pigment, any known material can be used as the white pigment. Specifically, inorganic oxides such as titanium oxide, zinc oxide and zirconium oxide; water-insoluble inorganic salts such as strontium titanate and barium sulfate; water-dispersible resin particles (emulsions) such as hollow resin particles and non-hollow resin particles; ; etc. can be used.

<Other materials>
Additives such as antifoaming agents, thickeners, and antiseptics can be used as necessary in the pretreatment liquid of the present invention in order to obtain desired physical properties. When these additives are used, their blending amount is preferably 0.01 to 5% by mass, more preferably 0.01 to 3% by mass, based on the total amount of the pretreatment liquid. If it is added excessively, the function of the coagulant in the pretreatment liquid may be impaired, so the amount added is preferably within the above range.

<Physical properties of pretreatment liquid>
When the pretreatment liquid of the present invention contains water-insoluble particles having an average particle diameter (D ₅₀ ) of 1 μm or more, the content thereof is preferably 1% by mass or less relative to the total amount of the pretreatment liquid. By limiting the amount of the water-insoluble particles having an average particle size of 1 μm or more, the pretreatment liquid has a suitable storage stability over a long period of time.

In the present invention, the term "water-insoluble" means that the solubility in water at 25°C is less than 1% by mass. Specific examples of water-insoluble particles having an average particle size of 1 μm or more include organic pigments, inorganic oxides, water-insoluble inorganic salts, and water-dispersible resin particles (emulsions) that satisfy the particle size conditions. Among the materials described above, such as the aggregating agent (B) and the coloring agent, those having an average particle size of 1 μm or more are regarded as water-insoluble particles.

The pretreatment liquid of the present invention preferably has a viscosity at 25° C. of 5 to 200 mPa·s, more preferably 5 to 180 mPa·s, even more preferably 10 to 160 mPa·s. 140 mPa·s is particularly preferred. Since the pretreatment liquid satisfying the viscosity range described above can be uniformly applied to the base material, printed matter having excellent image quality and adhesion between the ink surface and the base material can be obtained. The viscosity of the pretreatment liquid can be determined according to the viscosity of the treatment liquid using, for example, an E-type viscometer (TVE25L viscometer manufactured by Toki Sangyo Co., Ltd.) or a B-type viscometer (TVB10 viscometer manufactured by Toki Sangyo Co., Ltd.). can be measured by

The static surface tension of the pretreatment liquid of the present invention is 20 from the viewpoint of providing suitable wettability on the substrate and forming a uniform pretreatment liquid layer to obtain prints with excellent image quality. It is preferably up to 45 mN/m, more preferably 22 to 40 mN/m, particularly preferably 25 to 35 mN/m. The static surface tension in this specification is a value based on the Wilhelmy method (plate method, vertical plate method) in an environment of 25° C., for example, an automatic surface tension meter DY-300 (manufactured by Kyowa Interface Science Co., Ltd.). and a platinum plate.

<Method for producing pretreatment liquid>
The pretreatment liquid of the present invention comprising the above components includes, for example, resin fine particles (A), aggregating agent (B), and, if necessary, an organic solvent, a surfactant, a pH adjuster, and the above-mentioned It is produced by adding an appropriately selected additive component such as, stirring and mixing, and then filtering as necessary. However, the method for producing the pretreatment liquid is not limited to the above. For example, when a white pigment is used as the colorant, a white pigment dispersion containing the white pigment and water may be prepared in advance and then mixed with the fine resin particles (A) and the coagulant (B).

<Water-based inkjet ink set>
The pretreatment liquid of the present invention can be used in combination with one or more water-based inkjet inks in the form of a water-based inkjet ink set. The constituent elements of the water-based inkjet inks constituting the water-based inkjet ink set are described below.
At least one of the water-based inkjet inks used in combination with the pretreatment liquid of the present invention preferably contains a pigment (P), a pigment dispersion resin (D), and water. More preferably, all the aqueous inkjet inks of the aqueous inkjet ink set contain a pigment (P), a pigment dispersing resin (D), and water.

<Pigment (P)>
The water-based inkjet ink used in combination with the pretreatment liquid of the present invention preferably contains a pigment (P) as a coloring material from the viewpoint of blocking resistance, water resistance, light resistance, weather resistance, gas resistance, and the like. . As the pigment (P), both known organic pigments and inorganic pigments can be used. These pigments are contained preferably in the range of 2 to 20% by mass, more preferably in the range of 2.5 to 15% by mass, and in the range of 3 to 10% by mass, based on the total amount of the aqueous ink. Inclusion is particularly preferred. In the case of white ink, the pigment content is preferably 3 to 40% by mass, more preferably 5 to 35% by mass, and more preferably 7 to 30% by mass with respect to the total amount of the white ink. is particularly preferred. By setting the content of the pigment to 2% by mass or more (3% by mass or more in the case of white ink), a printed matter having sufficient color development and vividness can be obtained. In addition, by setting the pigment content to 20% by mass or less (40% by mass or less in the case of white ink), the viscosity of the water-based ink can be kept within a range suitable for inkjet printing, and the storage stability of the water-based ink can be improved. As a result, ejection stability can be ensured over a long period of time.

Examples of cyan organic pigments that can be used in the water-based ink used in combination with the pretreatment liquid of the present invention include C.I. I. Pigment Blue 1, 2, 3, 15:3, 15:4, 15:6, 16, 22, 60, 64, 66. Among them, C.I. I. At least one selected from the group consisting of Pigment Blue 15:3 and 15:4 is preferred.

Further, as a magenta organic pigment, for example, C.I. I. Pigment Red 5, 7, 12, 22, 23, 31, 48(Ca), 48(Mn), 49, 52, 53, 57(Ca), 57:1, 112, 122, 146, 147, 150, 185 , 202, 209, 238, 242, 254, 255, 266, 269, 282, C.I. I. Pigment Violet 19, 23, 29, 30, 37, 40, 43, 50 can be used. Among them, C.I. I. Pigment Red 122, 150, 166, 185, 202, 209, 266, 269, 282, and C.I. I. One or more selected from the group consisting of Pigment Violet 19 is preferred.

From the viewpoint of further enhancing the color developability, it is also preferable to use a solid solution pigment containing a quinacridone pigment as the magenta organic pigment. Specifically, C.I. I. Pigment Red 122 and C.I. I. Pigment Violet 19, a solid solution pigment containing C.I. I. Pigment Red 202 and C.I. I. Pigment Violet 19, a solid solution pigment containing C.I. I. Pigment Red 209 and C.I. I. Pigment Violet 19, a solid solution pigment containing C.I. I. Pigment Red 282 and C.I. I. Pigment Violet 19, a solid solution pigment containing C.I. I. Pigment Red 122 and C.I. I. Pigment Red 150, C.I. I. Pigment Red 122 and C.I. I. Pigment Red 185, a solid solution pigment containing C.I. I. Pigment Red 122 and C.I. I. Pigment Red 269 and other solid solution pigments.

Further, as a yellow organic pigment, for example, C.I. I. Pigment Yellow 12, 13, 14, 17, 20, 24, 74, 83, 86, 93, 94, 95, 109, 110, 117, 120, 125, 128, 137, 138, 139, 147, 148, 150, 151, 154, 155, 166, 168, 180, 185, 213 are available. Among them, C.I. I. At least one selected from the group consisting of Pigment Yellow 12, 13, 14, 74, 120, 180, 185, and 213 is preferred.

As black organic pigments, for example, aniline black, lumogen black, and azomethine azo black can be used. A black pigment can also be obtained by mixing a plurality of chromatic pigments such as the cyan pigment, magenta pigment and yellow pigment described above and the orange pigment, green pigment and brown pigment described below.

Special color pigments such as orange pigments, green pigments, and brown pigments can also be used in water-based inkjet inks. Specifically, C.I. I. Pigment Orange 16, 36, 43, 51, 55, 59, 61, 64, 71, C.I. I. Pigment Green 7, 36, 43, 58, Pigment Brown 23, 25, 26 and the like.

Inorganic pigments that can be used in water-based inkjet inks are not particularly limited. For example, carbon black and iron oxide can be used as black pigments, and titanium oxide can be used as white pigments.

Examples of carbon black include furnace black, channel black, and acetylene black. Among these carbon blacks, those having a primary particle diameter of 11 to 50 nm, a BET specific surface area of 50 to 400 m ² /g, a volatile content of 0.5 to 10% by mass, and a pH of 2 to 10 are preferred. preferred. As a commercial product having such properties, for example, No. 25, 30, 33, 40, 44, 45, 52, 850, 900, 950, 960, 970, 980, 1000, 2200 B2300, 2350, 2600; MA7, MA8, MA77, MA100, MA230 (manufactured by Mitsubishi Chemical Corporation ), RAVEN760UP, 780UP, 860UP, 900P, 1000P, 1060UP, 1080UP, 1255 (manufactured by Birla Carbon), REGAL330R, 400R, 660R, MOGULL (manufactured by Cabot), Nipex160IQ, 170IQ, 35, 75; 35, Special Black 350, 550; Nerox 305, 500, 505, 600, 605 (manufactured by Orion Engineered Carbons), any of which are preferably used. can be done.

In addition, as titanium oxide suitably used as a white pigment, both an anatase type and a rutile type can be used, but it is preferable to use the rutile type in order to increase the hiding power of printed matter. Titanium oxide produced by any method such as the chlorine method and the sulfuric acid method may be selected, but titanium oxide produced by the chlorine method is preferably used because of its high whiteness.

Also, the titanium oxide is preferably surface-treated with an inorganic compound and/or an organic compound. Examples of inorganic compounds include compounds of silicon (Si), aluminum, zirconium, tin, antimony, titanium, and hydrated oxides thereof. Examples of organic compounds include polyhydric alcohols, alkanolamines or derivatives thereof, higher fatty acids or metal salts thereof, and organometallic compounds. Among these, polyhydric alcohols or derivatives thereof are preferably used because they can make the surface of titanium oxide highly hydrophobic and improve the storage stability of the ink.

In addition, in the water-based inkjet ink used in combination with the pretreatment liquid of the present invention, a plurality of the above pigments can be mixed and used in order to keep the hue and coloring property of the printed matter within a suitable range. For example, one selected from cyan organic pigments, violet organic pigments, magenta organic pigments, orange organic pigments, and brown organic pigments in order to improve the color tone at low printing rates for black inks using carbon black pigments. A small amount of the above pigments may be added.

<Pigment dispersion resin (D)>
As a method for stably dispersing and holding a pigment in an aqueous ink, (1) a method in which a water-soluble pigment dispersing resin is adsorbed on the surface of the pigment to disperse it; (3) a method of chemically and physically introducing a hydrophilic functional group onto the surface of the pigment and dispersing it in the ink without a dispersing resin or surfactant (self-dispersing pigment); ) A method of coating a pigment with a water-insoluble resin and, if necessary, further dispersing it in ink using another water-soluble pigment dispersing resin or surfactant.

In the water-based ink used in combination with the pretreatment liquid of the present invention, the method (1) or (4) above, that is, the method using the pigment dispersion resin (D) is selected, and the pigment dispersion resin ( It is preferable that D) contains a monomer having an aromatic ring structure in an amount of 20 to 90% by mass based on the total amount of monomers constituting the pigment dispersion resin (D). This is due to the adhesion and image quality between the ink surface and the substrate due to the π-cation interaction formed by the aromatic ring contained in the pigment dispersion resin (D) and the flocculant (B) contained in the pretreatment liquid. and to secure and improve the storage stability of water-based inkjet inks containing water-soluble organic solvents. In this specification, the term "pigment dispersion resin (D)" collectively refers to the water-soluble pigment dispersion resin used in the above methods (1) and (4) and the water-insoluble resin used in the above method (4). defined as the term The term "water-insoluble resin" refers to a target resin whose aqueous solution of 1% by mass at 25°C is not transparent when viewed with the naked eye.

Among the above methods, the method (1) using a water-soluble pigment dispersing resin is particularly preferable for the water-based ink used in combination with the pretreatment liquid of the present invention. By selecting and studying the composition and molecular weight of the monomers that make up the resin, it is possible to easily adjust the ability of the resin to adsorb the pigment and the charge of the pigment dispersion resin (D), resulting in improved storage stability of the ink. Also, it is possible to control the pigment aggregation ability of the pretreatment liquid of the present embodiment.

The type of the pigment dispersion resin (D) is not particularly limited. Acid resins, polyurethane resins, and polyester resins (polycondensates of polyhydric carboxylic acids and polyhydric alcohols) can be used. Among them, acrylic resins, styrene-acrylic resins, polyurethane resins, and polyester resins are particularly preferable in view of the wide selection of materials containing monomers having an aromatic ring structure and the ease of synthesis. The above pigment dispersion resin (D) can be synthesized by a known method, or a commercially available product can be used.

As described above, the pigment dispersion resin (D) preferably contains 20 to 90% by mass, more preferably 20 to 80% by mass, of the monomers having an aromatic ring structure among the total monomers used in its synthesis. is more preferable, and 20 to 70% by mass is particularly preferable. By keeping the amount of the aromatic ring structure within the above range, the effect of improving the adhesion between the ink surface and the substrate and the image quality using the π-cation interaction, and the effect of water-based inks containing water-soluble organic solvents with low boiling points. The effect of ensuring/improving the storage stability is favorable.

The pigment dispersion resin (D) preferably contains an alkyl group having 10 to 36 carbon atoms in addition to the aromatic ring structure. This is because by setting the number of carbon atoms in the alkyl group to 10 to 36, it is possible to reduce the viscosity of the pigment dispersion, further improve the image quality, and improve the storage stability. The number of carbon atoms in the alkyl group is preferably 12 to 30 carbon atoms, more preferably 12 to 30 carbon atoms, from the viewpoint of optimizing compatibility with water-soluble organic solvents in water-based inks and improving drying properties of printed matter. 18-24. As long as the alkyl group has 10 to 36 carbon atoms, it may be linear or branched, but linear is preferred. Examples of linear alkyl groups include a lauryl group (C12), a myristyl group (C14), a cetyl group (C16), a stearyl group (C18), an aralkyl group (C20), a behenyl group (C22), a lignoceryl group (C24), and cerotoyl. group (C26), montanyl group (C28), melisyl group (C30), dotriacontanoyl group (C32), tetratriacontanoyl group (C34), hexatriacontanoyl group (C36) and the like.

The content of the monomer containing an alkyl chain having 10 to 36 carbon atoms contained in the pigment dispersion resin (D) reduces the viscosity of the pigment dispersion and the scratch resistance, drying property, and blocking resistance of the printed matter. It is preferably 5 to 60% by mass, more preferably 15 to 55% by mass, and particularly preferably 25 to 50% by mass, from the viewpoint of achieving both gloss and gloss.

It is also preferable that the pigment dispersion resin (D) contains an alkylene oxide group in addition to the aromatic ring structure. By introducing an alkylene oxide group, the hydrophilicity/hydrophobicity of the pigment dispersion resin (D) can be arbitrarily adjusted, and the storage stability of the water-based ink can be improved. It induces hydrogen bonding with the fine resin particles (A) and the impermeable base material, and particularly improves the adhesion between the ink surface and the base material in the printed matter. When a water-soluble pigment dispersing resin is used as the pigment dispersing resin (D), it is preferable to select an ethylene oxide group as the alkylene oxide group in order to suitably exhibit the above functions. Similarly, when a water-insoluble resin is used as the pigment dispersion resin (D), it is preferable to select a propylene oxide group as the alkylene oxide group.

The content of the monomer having an alkylene oxide group contained in the pigment dispersion resin (D) affects the viscosity reduction of the pigment dispersion, the storage stability of the water-based ink, and the adhesion between the ink surface and the substrate in the printed matter. from the viewpoint of compatibility, of the total monomers used in resin synthesis, it is preferably 5 to 40% by mass, more preferably 10 to 35% by mass, and 15 to 30% by mass. Especially preferred.

As the method for stably dispersing and holding the pigment in the water-based ink, the above method (1) is selected, that is, when a water-soluble pigment dispersion resin is used as the pigment dispersion resin (D), the solubility is preferably neutralized with a base in the pigment dispersion resin (D). However, if the base is added in excess, if the pretreatment liquid contains cationic components, the cationic components will be neutralized, and sufficient effects cannot be exhibited. It is necessary to pay attention. Whether the added amount of the base is excessive can be confirmed, for example, by preparing a 10% by mass aqueous solution of the pigment dispersion resin (D) and measuring the pH of the aqueous solution. Above all, the aqueous solution preferably has a pH of 7 to 11.5, more preferably 7.5 to 11, in order to sufficiently exhibit the function of the pretreatment liquid.

Examples of the base for neutralizing the pigment dispersion resin (D) include alkanolamine such as diethanolamine, triethanolamine and N-methyldiethanolamine; ammonia water; lithium hydroxide, sodium hydroxide, potassium hydroxide and the like. alkali metal hydroxides; alkali metal carbonates such as lithium carbonate, sodium carbonate, sodium hydrogencarbonate and potassium carbonate;

The above method (1) is selected as the method for stably dispersing and holding the pigment in the ink, that is, when a water-soluble pigment dispersion resin is used as the pigment dispersion resin (D), the acid value thereof is 30 to 375 mgKOH. /g is preferred. By keeping the acid value within the above range, the solubility of the pigment dispersion resin (D) in water can be ensured, and the interaction between the pigment dispersion resin (D) is favorable, so that the pigment dispersion This is because the viscosity of the liquid can be suppressed. When the acid value is 30 mgKOH/g or more, the solubility in water is good, and the viscosity of the pigment dispersion can be suppressed. The acid value of the pigment dispersion resin (D) is more preferably 65-340 mgKOH/g, still more preferably 100-300 mgKOH/g, and particularly preferably 135-270 mgKOH/g.

Furthermore, the acid value of the pigment dispersion resin (D) is within the above range, so that the cationic group of the vinyl monomer (c1) having the cationic group of the water-soluble cationic resin (c) in the pretreatment liquid and the amino group of the vinyl monomer (c2) having an amino group interacts with the anionic group in the pigment dispersion, the wettability and fixation of the inkjet ink to the printed matter coated with the pretreatment liquid It is possible to obtain a printed matter with improved print quality and excellent print image quality.

On the other hand, when the above method (4) is selected, that is, when a water-insoluble resin is used as the pigment dispersion resin (D), the acid value is preferably 0 to 100 mgKOH/g, and 5 to 90 mgKOH/g. more preferably 10 to 80 mgKOH/g. This is because by setting the acid value within the above range, a printed material having excellent blocking resistance and scratch resistance can be obtained. The acid value of the pigment dispersion resin (D) is the number of mg of potassium hydroxide (KOH) required to neutralize the acid contained in 1 g of the pigment dispersion resin (D), and ethanol/toluene. It is a value obtained by titration with a KOH solution in a mixed solvent. The measurement can be performed using, for example, "potentiometric automatic titrator AT-610" manufactured by Kyoto Electronics Industry Co., Ltd.

The weight average molecular weight of the pigment dispersion resin (D) is preferably in the range of 1,000 to 300,000, more preferably in the range of 5,000 to 200,000. When the weight-average molecular weight is within the above range, the pigment is stably dispersed in water, thereby improving the storage stability of the water-based ink and facilitating adjustment of the viscosity when used in the water-based ink. When the weight average molecular weight is 1,000 or more, the pigment dispersing resin (D) is difficult to dissolve in the water-soluble organic solvent added to the water-based ink, and the dispersing resin adsorbs to the pigment. and improve the storage stability of the ink. When the weight-average molecular weight is 300,000 or less, not only is the viscosity at the time of dispersion kept low, but also the ejection stability from the inkjet head is improved, enabling stable printing over a long period of time.

In the water-based ink used in combination with the pretreatment liquid of the present invention, the blending amount of the pigment dispersing resin (D) is preferably 2 to 60% by mass based on the pigment. By setting the amount of the pigment dispersion resin (D) to be 2 to 60% by mass based on the pigment, the viscosity of the pigment dispersion is suppressed, and the storage stability and dispersion stability of the pigment dispersion and water-based ink are improved. When mixed with the pretreatment liquid of the present embodiment, aggregation occurs immediately. The ratio of the pigment to the pigment dispersing resin (D) is more preferably 4 to 55% by mass, more preferably 5 to 50% by mass.

<Water-soluble organic solvent>
The water-based inkjet ink used in combination with the pretreatment liquid of the present invention preferably contains a water-soluble organic solvent. Further, the amount of the water-soluble organic solvent having a boiling point of 250° C. or higher under 1 atmosphere is preferably 5% by mass or less (may be 0% by mass) relative to the total amount of the water-based inkjet ink. By reducing the amount of water-soluble organic solvent with a high boiling point to 5% by mass or less, the drying property and ejection stability of the water-based inkjet ink are improved, and when combined with the pretreatment liquid, there is no image quality defect such as bleeding. , a water-based ink having good anti-blocking properties can be obtained. From the viewpoint of further improving image quality and blocking resistance, the amount of the water-soluble organic solvent having a boiling point of 250° C. or higher under 1 atmosphere is preferably 2% by mass or less, and 1% by mass or less. is more preferable (both may be 0% by mass).

For the same reason, the amount of the water-soluble organic solvent having a boiling point of 220° C. or higher under 1 atm is preferably 5% by mass or less (may be 0% by mass) relative to the total amount of the water-based ink, and is preferably 2% by mass. It is particularly preferable that the content is less than or equal to (may be 0% by mass). The amount of the water-soluble organic solvent having a boiling point of 220°C or higher at 1 atmosphere is calculated including the water-soluble organic solvent having a boiling point of 250°C or higher at 1 atmosphere.

The water-soluble organic solvent contained in the water-based inkjet ink preferably has a weighted boiling point average under 1 atmosphere of 145 to 215°C, more preferably 150 to 200°C, and 155 to 190°C. is particularly preferred. By keeping the weighted boiling point average value of the water-soluble organic solvent within the above range, when combined with the pretreatment liquid of the present embodiment, high-quality images can be obtained even in high-speed printing, and ejection stability can be improved. will also be excellent. The calculation of the weighted average boiling point includes water-soluble organic solvents with a boiling point of 250° C. or higher and water-soluble organic solvents with a boiling point of 220° C. or higher at 1 atmosphere. In addition, the weighted boiling point average value under 1 atmosphere is obtained by adding the product of the boiling point under 1 atmosphere calculated for each water-soluble organic solvent and the mass ratio with respect to the total water-soluble organic solvent. is the value

The boiling point under 1 atmosphere can be measured by using a thermal analysis device such as DSC (differential scanning calorimetry).

The total amount of the water-soluble organic solvent used in the water-based inkjet ink is preferably 3-40% by mass based on the total amount of the water-based inkjet ink. Furthermore, from the viewpoint of obtaining prints with excellent image quality and adhesion between the ink surface and the base material, ensuring ejection stability from the nozzle and sufficient wettability and dryness when combined with the pretreatment liquid. , more preferably 5 to 35% by mass, and particularly preferably 8 to 30% by mass or less. By setting the total amount of the water-soluble organic solvent to 3% by mass or more, the ink has good moisture retention properties, and the ink has excellent ejection stability. In addition, by setting the content of the water-soluble organic solvent to 40% by mass or less, an ink with good drying properties can be obtained, resulting in a printed matter with excellent image quality. From the viewpoint of compatibility and affinity with pigment dispersion resin (D), binder resin (E) described later, and material components such as surfactants, a glycol ether-based solvent and/or an alkyl polyol-based solvent are included. is preferred.

Examples of glycol ether-based solvents that are suitably used and have a boiling point of less than 250°C under 1 atmosphere include ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, Diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl Ethers, glycol monoalkyl ethers such as dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, 1,2-butylene glycol monomethyl ether, 1,3-butylene glycol monomethyl ether; diethylene glycol diethyl ether, diethylene glycol isopropyl methyl ether, diethylene glycol Glycol dialkyl ethers such as butyl methyl ether, triethylene glycol dimethyl ether, and triethylene glycol methyl ethyl ether can be mentioned.

In particular, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, Propylene Glycol Monoethyl Ether, Propylene Glycol Monopropyl Ether, Dipropylene Glycol Monomethyl Ether, Dipropylene Glycol Monoethyl Ether, Dipropylene Glycol Monopropyl Ether, Dipropylene Glycol Monobutyl Ether, 1,2-Butylene Glycol Monomethyl Ether, 1,3 - butylene glycol monomethyl ether, diethylene glycol butyl methyl ether, triethylene glycol methyl ethyl ether are preferably selected.

Examples of alkyl polyol solvents having a boiling point under 1 atmosphere of less than 250° C. include 1,2-ethanediol (ethylene glycol), 1,2-propanediol (propylene glycol), 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 2,2-dimethyl-1, 3-propanediol, 2-methyl-1,3-propanediol, 2-ethyl-2-methyl-1,3-propanediol, 3-methyl-1,3-butanediol, 2-methylpentane-2,4 -diol, 2-ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol.

Among the above alkyl polyol solvents, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3- Preference is given to choosing butanediol, 1,2-pentanediol, 1,2-hexanediol, diethylene glycol, dipropylene glycol.

<Binder resin (E)>
The water-based inkjet ink used in combination with the pretreatment liquid of the present invention preferably contains a binder resin (E). The form of the binder resin (E) may be any of a water-soluble resin, an emulsion, and a dispersion which is an intermediate form between the two. A combination of the above may be used. For example, emulsions and dispersions can lower the viscosity of water-based inkjet inks and can contain a larger amount of resin, so they are suitable for increasing the durability of printed matter. In addition, water-based inkjet inks using a water-soluble resin as a binder resin are excellent in ejection stability and image quality of printed matter when combined with the pretreatment liquid of the present embodiment.

Regarding the types of the binder resin (E), (meth)acrylic resin, styrene (meth)acrylic resin, (anhydride) maleic acid resin, styrene (anhydride) maleic acid resin, olefin (anhydrous) maleic acid resin, polyurethane resin, Polyester resins, polyolefin resins, and the like can all be suitably used. Among them, from the viewpoint of the storage stability of water-based inkjet inks, and the adhesion and abrasion resistance between the ink surface and the substrate in printed matter when combined with the pretreatment liquid of the present embodiment, (meth)acrylic resins, styrene (Meth) acrylic resins, polyurethane resins and polyolefin resins are preferably used.

When an emulsion is used as the binder resin (E), the minimum film-forming temperature ( MFT) is preferably 50° C. or higher.

The MFT can be measured, for example, by an MFT tester manufactured by Tester Sangyo Co., Ltd. Specifically, after coating a 25% by mass aqueous solution of resin fine particles on the film so that the WET film thickness is 300 μm, it is left to stand on the tester while applying a temperature gradient, and after drying, a white precipitate is formed. The temperature at the boundary between the generated area and the area where the transparent resin film is formed is defined as MFT.

Further, when a water-soluble resin and dispersion are used as the binder resin (E), from the viewpoint of achieving both the ejection stability of the water-based inkjet ink and the scratch resistance of the printed matter, the weight average molecular weight is 5,000 to 80, 000, more preferably 8,000 to 60,000, and particularly preferably 10,000 to 50,000. For the same reason, the water-soluble resin and dispersion preferably have an acid value of 5 to 80 mgKOH/g, more preferably 10 to 50 mgKOH/g.

The content of the binder resin (E) in the total amount of the water-based inkjet ink is preferably 1 to 20% by mass, more preferably 2 to 15% by mass, in terms of solid content, based on the total amount of the water-based inkjet ink. It is preferably 3 to 10% by mass.

<Surfactant>
The water-based ink used in combination with the pretreatment liquid of the present invention preferably contains a surfactant for the purpose of adjusting surface tension and improving image quality. On the other hand, if the surface tension is too low, the nozzle surface of the inkjet head will be wetted with water-based ink, impairing ejection stability. From the viewpoint of ensuring wettability to the substrate and optimizing ejection stability from the nozzle, it is preferable to use a siloxane-based, acetylenediol-based, fluorine-based, or polyoxyalkylene alkyl ether-based surfactant. It is particularly preferred to use acetylene diol-based surfactants. The amount of surfactant added is preferably 0.01 to 5.0% by mass, more preferably 0.05 to 3.0% by mass, based on the total amount of the water-based ink.

Surfactants can be synthesized by known methods, or commercially available products can be used. When the surfactant is selected from commercially available products, for example, acetylene diol-based surfactants and polyoxyalkylene alkyl ether-based surfactants can be preferably selected from those listed above as surfactants that can be used in the pretreatment liquid. . As siloxane surfactants, BY16-201, FZ-77, FZ-2104, FZ-2110, FZ-2162, F-2123, L-7001, L-7002, SF8427, SF8428, SH3749, SH8400, 8032ADDITIVE , SH3773M (manufactured by Dow Corning Toray), Tegoglide410, Tegoglide432, Tegoglide435, Tegoglide440, Tegoglide450, Tegotwin4000, Tegotwin4100, Tegowet250, Tegowet2 60, Tegowet270, Tegowet280 (manufactured by Evonik Degussa), SAG-002, SAG-503A (Nissin Chemical Kogyosha), BYK-331, BYK-333, BYK-345, BYK-346, BYK-347, BYK-348, BYK-349, BYK-UV3500, BYK-UV3510 (manufactured by BYK-Chemie), KF-351A, KF-352A, KF-353, KF-354L, KF355A, KF-615A, KF-640, KF-642, KF-643 (manufactured by Shin-Etsu Chemical Co., Ltd.), etc., as fluorine-based surfactants, ZonylTBS, FSP , FSA, FSN-100, FSN, FSO-100, FSO, FS-300, Capstone FS-30, FS-31 (DuPont), PF-151N, PF-154N (manufactured by Omnova) and the like can be used. In addition, said surfactant may be used individually and may use 2 or more types together.

The surfactant used in the water-based ink and the surfactant used in the pretreatment liquid may be the same or different. When different surfactants are used, it is preferable to determine the blending amount while paying attention to the surface tension of both.

<Water>
As the water contained in the water-based ink used in combination with the pretreatment liquid of the present invention, ion-exchanged water (deionized water) is preferably used instead of general water containing various ions.

The content of water that can be used in water-based inks is preferably in the range of 20 to 90% by mass of the total mass of the ink.

<Other ingredients>
The water-based ink used in combination with the pretreatment liquid of the present invention may contain, in addition to the above components, a pH adjuster to obtain the ink having desired physical property values. can be arbitrarily selected. Alkanolamines such as dimethylethanolamine, diethanolamine, triethanolamine and N-methyldiethanolamine for basification; aqueous ammonia; alkali metal hydroxides such as lithium hydroxide, sodium hydroxide and potassium hydroxide; Alkali metal carbonates such as lithium, sodium carbonate, sodium hydrogencarbonate and potassium carbonate can be used. For acidification, hydrochloric acid, sulfuric acid, acetic acid, citric acid, maleic acid, maleic anhydride, succinic acid, tartaric acid, malic acid, phosphoric acid, boric acid, fumaric acid, malonic acid, ascorbic acid, glutamic acid, etc. are used. be able to. The above pH adjusters may be used alone, or two or more of them may be used in combination.

The blending amount of the pH adjuster is preferably 0.01 to 5% by mass, more preferably 0.1 to 3% by mass, more preferably 0.2 to 1.5% by mass, based on the total amount of the water-based inkjet ink. is most preferred. By keeping it within the above range, it does not cause a pH change due to dissolution of carbon dioxide in the air, etc., and inhibits the flocculating effect of the flocculant (B) when the pretreatment liquid and water-based ink come into contact. It is preferable because the effects of the present invention can be favorably exhibited without the use of the material.

In addition to the above components, the water-based ink may optionally contain additives such as antifoaming agents, antiseptics, infrared absorbers, and ultraviolet absorbers in order to obtain inks with desired physical properties. can be added. As an example of the amount of these additives to be added, 0.01 to 5% by mass is suitable with respect to the total mass of the ink.

<Setting water-based inkjet ink>
The water-based inkjet ink used in combination with the pretreatment liquid of the present invention may be used in a single color, but may also be used as a set of water-based inkjet inks in which a plurality of colors are combined according to the application. Although the combination is not particularly limited, a full-color image can be obtained by using three colors of cyan, yellow, and magenta. In addition, by adding black ink, the feeling of blackness can be improved, and the visibility of characters and the like can be improved. Furthermore, color reproducibility can be improved by adding colors such as orange and green. With film substrates, which are an example of impermeable substrates, clear images can be obtained by printing white ink on transparent films. and visibility can be improved, so they are preferably combined.

<Method for producing water-based inkjet ink>
A water-based inkjet ink containing the components described above is produced, for example, through the following processes. However, the method for producing the water-based inkjet ink is not limited to the following.

(1) Production of Pigment Dispersion When a water-soluble pigment dispersion resin is used as the pigment dispersion resin (D), the water-soluble pigment dispersion resin, water, and, if necessary, a water-soluble organic solvent are mixed and stirred, A water-soluble pigment dispersion resin mixture is prepared. A pigment is added to the water-soluble pigment dispersion resin mixed solution, mixed and stirred (premixed), and then dispersed using a disperser. Thereafter, centrifugation, filtration, and adjustment of the solid content concentration are performed as necessary to obtain a pigment dispersion.

Further, when producing a dispersion liquid of a pigment coated with a water-insoluble resin, the water-insoluble resin is dissolved in an organic solvent such as methyl ethyl ketone in advance, and if necessary, the water-insoluble resin is neutralized. to make. A pigment and water are added to the water-insoluble resin solution, mixed and stirred (premixed), and then dispersed using a disperser. Thereafter, the organic solvent is removed by distillation under reduced pressure, and if necessary, centrifugation, filtration, and adjustment of the solid content concentration are performed to obtain a pigment dispersion.

The dispersing machine used in dispersing the pigment may be any dispersing machine that is generally used, and examples thereof include ball mills, roll mills, sand mills, bead mills and nanomizers. Among the above, a bead mill is preferably used, and specifically, it is commercially available under trade names such as super mill, sand grinder, agitator mill, grain mill, dyno mill, pearl mill and cobol mill.

Methods for controlling the particle size distribution of the pigment dispersion include reducing the size of the grinding media of the disperser listed above, changing the material of the grinding media, increasing the filling rate of the grinding media, and stirring members ( agitator), lengthening the dispersion treatment time, classifying with a filter, centrifuge, or the like after dispersion treatment, and a combination of these techniques. In order to keep the pigment within a suitable particle size range, it is preferable to set the diameter of the grinding media of the disperser to 0.1 to 3 mm. Glass, zircon, zirconia, and titania are preferably used as the material of the grinding media.

(2) Preparation of water-based inkjet ink Next, a water-soluble organic solvent, water, and, if necessary, the above-mentioned binder resin, surfactant, and other additives are added to the pigment dispersion, and stirred and mixed. . The mixture may be stirred and mixed while being heated in the range of 40 to 100° C., if necessary.

(3) Removal of Coarse Particles Coarse particles contained in the mixture are removed by a method such as filtration separation or centrifugation to obtain an aqueous inkjet ink. As a method for filtration separation, a known method can be appropriately used. The pore size of the filter is not particularly limited as long as it can remove coarse particles and dust, but it is preferably 0.3 to 5 μm, more preferably 0.5 to 3 μm. When performing filtration, a single kind of filter may be used, or multiple kinds of filters may be used in combination.

<Characteristics of water-based inkjet ink>
The viscosity of the water-based inkjet ink is preferably adjusted to 3 to 20 mPa·s at 25°C. Within this viscosity range, stable ejection characteristics can be exhibited particularly from an inkjet head having a frequency of 4 to 10 kHz to a high frequency inkjet head of 10 to 70 kHz. In particular, by setting the viscosity at 25° C. to 4 to 10 mPa·s, stable ejection can be achieved even when used for an inkjet head having a design resolution of 600 dpi or more.

In addition, the said viscosity can be measured by a conventional method. Specifically, it can be measured using an E-type viscometer (TVE25L type viscometer manufactured by Toki Sangyo Co., Ltd.) using 1 mL of ink.

In addition, this embodiment provides a water-based inkjet ink that can be stably ejected, and when combined with the pretreatment liquid of the present invention, a printed matter with excellent adhesion between the ink surface and the substrate and excellent image quality can be obtained. The water-based inkjet ink preferably has a static surface tension at 25° C. of 18 to 35 mN/m, more preferably 19 to 32 mN/m, particularly preferably 20 to 28 mN/m. In addition, from the viewpoint of preventing bleeding and color mixing of printed matter and obtaining printed matter with particularly excellent image quality, by adjusting the type and amount of water-soluble organic solvent and surfactant, the surface tension of the water-based ink of this embodiment is preferably less than or equal to the surface tension of the pretreatment liquid. The static surface tension in the present embodiment can be measured by the platinum plate method in an environment of 25° C. using, for example, a surface tensiometer (CBVP-Z manufactured by Kyowa Interface Science Co., Ltd.).

For the same reason as above, the water-based inkjet ink preferably has a dynamic surface tension of 25 to 40 mN/m at 25° C. for 10 msec, more preferably 28 to 38 mN/m, more preferably 30 to 36 mN/m. m is particularly preferred. The dynamic surface tension in this embodiment can be measured by the maximum bubble pressure method in a 25° C. environment using a bubble pressure dynamic surface tension meter BP100 manufactured by Kruss.

In the water-based inkjet ink, the average secondary particle diameter (D ₅₀ ) of the pigment is preferably 40 nm to 500 nm, more preferably 50 nm to 400 nm, and particularly preferably 60 nm to 300 nm. In order to keep the average secondary particle size within the preferred range, the pigment dispersion treatment step may be controlled as described above.

<Manufacturing method of printed matter>
As a method for producing a printed matter with a water-based inkjet ink set in which the pretreatment liquid of the present invention and the water-based inkjet ink are combined, a step of printing the pretreatment liquid on a non-permeable substrate; A step of printing the water-based inkjet ink on the portion of the material printed with the pretreatment liquid by inkjet printing using a one-pass printer method, and drying the impermeable substrate printed with the water-based inkjet ink. is preferably used. Note that the above steps are preferably performed in this order.

A method for producing a printed matter using the water-based inkjet ink set will be described below.

<Method of printing pretreatment liquid>
When producing prints using the pretreatment liquid of the present invention, the pretreatment liquid is preferably printed on the impermeable substrate prior to printing the water-based inkjet ink. As the printing method, either a method of printing without contacting the base material such as inkjet printing or a method of printing by contacting the base material with a pretreatment liquid may be employed. In addition, when selecting a printing method that contacts the pretreatment liquid as the printing method of the pretreatment liquid, there are roller types such as offset gravure coater, gravure coater, doctor coater, bar coater, blade coater, flexo coater, and roll coater. It can be used preferably.

<Drying method after pretreatment liquid printing>
When printing using the pretreatment liquid of the present invention, the pretreatment liquid is printed on a non-permeable substrate, the pretreatment liquid on the substrate is dried, and then the water-based inkjet ink is printed. Alternatively, the water-based inkjet ink may be printed before the pretreatment liquid on the substrate is completely dried. Above all, it is preferable to completely dry the pretreatment liquid before printing the water-based inkjet ink, that is, to completely remove the liquid component of the pretreatment liquid. This is because by printing with the water-based inkjet ink after the pretreatment liquid has completely dried, the water-based inkjet ink that lands later does not cause drying failure, and a printed matter with excellent scratch resistance can be obtained.

The method for drying the pretreatment liquid of the present invention is not particularly limited, and conventionally known methods such as heat drying, hot air drying, infrared drying, microwave drying and drum drying can be used. Although the above drying methods may be used alone or in combination, it is preferable to use a hot air drying method in order to reduce damage to the impermeable substrate and to dry efficiently. In addition, from the viewpoint of preventing damage to the substrate and bumping of the liquid component in the pretreatment liquid, when using the heat drying method, the drying temperature should be 35 to 100 ° C., and the hot air drying method should be used. In this case, it is preferable to set the hot air temperature to 50 to 150°C.

<Method for printing water-based inkjet ink>
The water-based inkjet ink is preferably applied by one-pass inkjet printing to the pretreatment liquid-printed portion of the non-permeable substrate. The designed resolution of the inkjet head used in the 1-pass inkjet printing is preferably 600 dpi (Dots Per Inch) or more, more preferably 720 dpi or more, from the viewpoint of obtaining an image with excellent image quality.

<Drying method after water-based inkjet ink printing>
In order to dry the water-based ink and the undried pretreatment liquid after printing with the water-based ink-jet ink, it is preferable to include a step of drying the impermeable substrate to which the water-based ink-jet ink has been applied. The drying method preferably used is the same as in the case of the pretreatment liquid.

<Print amount of pretreatment liquid and water-based inkjet ink>
It is preferable that the film thickness of the dried layer formed by printing the pretreatment liquid is 0.1 to 1.6 μm.
Alternatively, the print amount of the pretreatment liquid on the impermeable substrate is preferably 1 to 25 g/m ² . By keeping the film thickness and coating amount within the above range, mixed color bleeding is suppressed, and the drying property of the pretreatment liquid layer after coating is improved, so it does not adhere to the inside of the coating device and when printed matter is overlapped. It is possible to obtain a printed matter that prevents blocking, has no tackiness (stickiness), and has excellent abrasion resistance.

When printing with a water-based inkjet ink set, the ratio of the amount of water-based inkjet ink printed to the amount of pretreatment liquid printed is preferably 0.1 or more and 10 or less. The printing amount ratio is more preferably 0.5 or more and 9 or less, and particularly preferably 1 or more and 8 or less. By keeping the printing amount ratio within the above range, the texture of the substrate may change due to an excessive amount of pretreatment liquid, and the effect of the pretreatment liquid may become insufficient due to an excessive amount of water-based inkjet ink. It is possible to prevent deterioration of image quality that occurs.

<Base material>
When printing using the pretreatment liquid of the present invention, any known substrate can be used. For example, paper substrates such as coated paper, art paper, and lightly coated paper, thermoplastic materials such as polyvinyl chloride sheets, polyethylene terephthalate (PET) films, polypropylene films, polyethylene films, nylon films, polystyrene films, and polyvinyl alcohol films A resin substrate or a metal substrate such as an aluminum foil can be used. The surface of the base material may be smooth or uneven, and may be transparent, translucent, or opaque. Also, two or more of these base materials may be laminated together. Furthermore, a release adhesive layer or the like may be provided on the opposite side of the printed surface, or an adhesive layer or the like may be provided on the printed surface after printing. The shape of the base material may be roll-like or sheet-like.

Among them, a non-permeable base material or a low-permeability base material is preferable from the viewpoint of laminating and protecting the contents as a packaging material. Since the surface of the impermeable base material is subjected to a surface treatment such as corona treatment, it interacts with the amino groups of the water-soluble cationic resin (C) of the present invention, etc., thereby achieving high adhesion with the pretreatment liquid. It becomes possible to express. Therefore, the strength after lamination is improved, and the contents can be protected as a packaging material.
Non-permeable substrates are also particularly preferred. In the case of a non-permeable base material, the pretreatment liquid hardly permeates into the base material, so that the interaction with the inkjet ink increases and excellent print quality can be achieved. In this specification, the permeability of a recording medium is determined by the amount of water absorption measured by a dynamic scanning absorptiometer. Specifically, a recording medium having a pure water absorption of less than 1 g/m ² at a contact time of 100 msec, as measured by the following method, is defined as a “impermeable substrate” and is 1 to 10 g/m ² . Let the recording medium be a "hardly permeable base material".

The water absorption amount of the recording medium can be measured, for example, under the following conditions. Using KM500win manufactured by Kumagai Riki Kogyo Co., Ltd. as a dynamic scanning absorptiometer, under the conditions of 23 ° C. and 50% RH, using a recording medium of about 15 to 20 cm square, pure water under the conditions shown below. Measure the amount of transition.
・Measurement method: Spiral Scanning (Spiral Method)
・Measurement start radius: 20 mm
・Measurement end radius: 60 mm
・Contact time: 10 to 1,000msec
・ Number of sampling points: 19 (measured at approximately equal intervals with respect to the square root of the contact time)
・Scan interval: 7 mm
・Rotary table speed switching angle: 86.3 degrees ・Headbox conditions: width 5 mm, slit width 1 mm

In order to fully exhibit the functions of the pretreatment liquid of the present invention, the impermeable substrate is preferably a thermoplastic resin substrate, and particularly preferably a PET film, polypropylene film, polyethylene film, or nylon film. preferable.

In addition, from the viewpoint of improving the image quality by uniformly printing the pretreatment liquid of the present invention, and from the viewpoint of particularly improving the adhesion between the ink surface and the substrate, the non-permeable substrate as exemplified above. On the other hand, it is also preferable to apply a surface modification method such as corona treatment or plasma treatment.

<Coating treatment>
The printed matter produced using the pretreatment liquid of the present invention can be coated on the printed surface, if necessary. Specific examples of the coating treatment include coating and printing of a coating composition, and lamination by a dry lamination method, a solventless lamination method, an extrusion lamination method, or the like. may be combined.

In the case of applying a coating treatment to the printed material by coating and printing the coating composition, the coating and printing method may be a method of printing in a non-contact manner with respect to the substrate, such as inkjet printing, or Either of the methods in which the coating composition is brought into contact with the surface to be printed may be adopted. In addition, when a method of printing a coating composition on a substrate in a non-contact manner is selected, an ink ( Clear ink) is preferably used.

EXAMPLES The present invention will now be described more specifically with reference to examples and comparative examples. In the description below, "parts" and "%" represent "parts by mass" and "% by mass", respectively, unless otherwise specified. Numerical values in the table represent the number of copies unless otherwise specified.

<Production of pretreatment liquid>
[Production example of vinyl monomer (c1-1) having a cationic group]
77.6 parts of 2-methacryloyloxyethyl isocyanate and 0.06 part of p-methoxyphenol were added to a reaction vessel equipped with a gas inlet tube, a thermometer, a condenser and a stirrer. Then, dry air was passed through the reaction vessel, and the temperature was maintained at 25° C. or lower while stirring, and 37.6 parts of dimethylaminomethanol was added dropwise over 2 hours. After completion of dropping, the mixture was aged at 25° C. for 2 hours with stirring to obtain an intermediate of a vinyl monomer having a cationic group. Then, the mixture was dried in a reaction vessel, 39.3 parts of propyl chloride was added, and the mixture was stirred at room temperature for 12 hours to obtain a vinyl monomer (c1-1) having a cationic group. The vinyl monomer (c1-1) having a cationic group is represented by general formula (1), wherein R ¹ is a methyl group, Z is —O—CH ₂ —NH—C(=O)O—, R ² , R ³ and R ⁴ represent a methyl group, a methyl group and a propyl group, respectively. X ⁻ is a chloride ion and n=2.

[Production Example of Water-Soluble Cationic Resin C-1]
100 parts of ion-exchanged water and 100 parts of isopropyl alcohol (IPA) were charged into a reaction vessel equipped with a gas inlet tube, a thermometer, a condenser and a stirrer, and the contents were purged with nitrogen gas. The inside of the reaction vessel is heated to 80 ° C., and a mixture of 50 parts of acrylic ester DMC (manufactured by Mitsubishi Chemical) and 50 parts of DMAPAA-Q and 10 parts of a 5% aqueous solution of V-50 are added dropwise over 3 hours to polymerize. reacted. After completion of the dropwise addition, the mixture was reacted at 80° C. for 1 hour and aged. Furthermore, isopropyl alcohol and water in the liquid were distilled off, and water was added to adjust the solid content to 40%, thereby obtaining a water-soluble cationic resin C-1 (solid content: 40%). The weight average molecular weight of the water-soluble cationic resin C-1 measured by the above method was 89,000.

[Production Examples of Water-Soluble Cationic Resins C-2 to C-15]
Water-soluble cation resins C-2 to C-15 were produced in the same manner as for water-soluble cation resin C-1, except that the materials listed in Table 1 were used.

In addition, in the said manufacturing example, the detail of the raw material used is the following.
DMC: acrylic ester DMC (manufactured by Mitsubishi Chemical); methacrylate dimethylaminoethyl methyl chloride salt DMAPAA-Q: DMAPAA-Q (manufactured by KJ Chemicals); dimethylaminopropyl acrylamide methyl chloride quaternary salt QA: Blemmer QA (manufactured by NOF) ; methacrylic acid (2-hydroxyethyl) methylaminoethyl methyl chloride salt c1-1: dimethylaminoethoxycarbonylaminoethyl methacrylic acid DM: acrylic ester DM (manufactured by Mitsubishi Chemical); dimethylaminoethyl methacrylate DMAPAA: (manufactured by KJ Chemicals); Dimethylaminopropyl acrylamide DE: Acryester DE (manufactured by Mitsubishi Chemical); Diethylaminoethyl methacrylate PME-100: Blemmer PME-100 (manufactured by NOF); Methoxydiethylene glycol methacrylate M-3F: Trifluoroethyl methacrylate (manufactured by Kyoeisha Chemical)
St: Styrene (manufactured by Chuo Kasei)
V-50: V-50 (manufactured by Fujifilm Wako Pure Chemical Industries); 2,2′-azobis(2-methylpropionamidine) dihydrochloride

[Water-soluble cationic resin C-16]
Senka CP103 (polydiallyldimethylammonium chloride; weight average molecular weight: 140,000, solid content: 39%) was used as the water-soluble cationic resin C-16.

[Weight average molecular weight]
The elution curve and weight-average molecular weight (Mw) of the water-soluble cationic resin (C) are values obtained by GPC (gel permeation chromatography) in terms of standard polyethylene oxide, and the measurement conditions are as follows. The ratio of the high molecular weight component (H) and the low molecular weight component (L) shown in Table 2 was calculated from the area ratio using the values obtained by integrating both components with the retention time at which the molecular weight becomes 5,000 as a boundary.
Apparatus: HLC-8320GPC manufactured by Tosoh Corporation
Column: TSKgel G5000PWxl-CP
Detector: Differential refractive index detector Solvent: 0.1 mol/l sodium nitrate aqueous solution Solvent temperature: 40°C
Material concentration 0.1%
Material injection volume: 20 μL

[Example 1: Production of pretreatment liquid PR-1]
The following materials were put into a mixing vessel equipped with a stirrer, mixed at room temperature (25° C.) for 1 hour, heated to 50° C., and further mixed for 1 hour. Thereafter, the mixture was cooled to room temperature and filtered through a membrane filter with a pore size of 1 μm to obtain pretreatment liquid PR-1.
・NeoCrylXK-190 (solid content 40%) 77 parts ・DISPER BYK-190 (solid content 40%) 23 parts ・Water-soluble cationic resin C-1 (solid content 40%) 97.0 parts ・Water-soluble cationic resin C- 13 (solid content 40%) 3.0 parts BYK-3565 (solid content 100%) 5 parts Surfynol 465 (solid content 100%) 10 parts Proxel GXL (solid content 100%) 1 part Ion exchange water 784 copies

[Examples 2 to 14, Comparative Examples 1 to 5: Production examples of pretreatment solutions PR-2 to 19]
Pretreatment solutions PR-2 to PR-19 were produced in the same manner as pretreatment solution PR-1, except that the materials listed in Tables 2 and 3 were used.

In addition, in the said Example, the detail of the raw material used is the following. "NV" in the table represents solid content.
<Resin fine particles>
NeoCrylXK-190: Styrene-acrylic resin fine particles manufactured by DSM Coating Resins (glass transition temperature 32°C, solid content 40%)
Arrowbase SB-1230N: Unitika polyolefin resin fine particles (glass transition temperature -20 ° C., solid content 25%)
NeoRezR-9621: Urethane resin fine particles manufactured by DSM Coating Resins (glass transition temperature -31°C, solid content 38%)
DISPER BYK-190: Styrene-maleic acid copolymer manufactured by BYK-Chemie (solid content 40%)
<Surface conditioner>
BYK-3565: manufactured by BYK-Chemie, a (meth)acrylic resin having a polydimethylsiloxane chain structure and a polyether chain structure in side chains and a weight average molecular weight of 2,000 to 30,000 <surfactant>
Surfynol 465: Acetylene diol-based surfactant manufactured by Air Products (solid content 100%)
<Preservative>
Proxel GXL: 1,2-benzisothiazol-3-one manufactured by Arch Chemicals (solid content 100%)

<Evaluation of storage stability of pretreatment liquid>
For the pretreatment liquid produced above, using an E-type viscometer (TVE-20L manufactured by Toki Sangyo Co., Ltd.), the viscosity was measured under a 25 ° C environment, then placed in a sealed container and set to 60 ° C in a constant temperature machine. was stored at rest. The storage stability of the pretreatment liquid was evaluated by taking out the sealed container every week, measuring the viscosity after time in the same manner as described above, and calculating the viscosity change rate before and after the time. The evaluation criteria are as follows, and S, AA, and A are defined as the practically usable regions.
S: Viscosity change rate after storage for 4 weeks was less than ±2%.
AA: The viscosity change rate after storage for 4 weeks was less than ±5%, but the viscosity change rate after storage for 6 weeks was ±5% or more.
A: The viscosity change rate after storage for 3 weeks was less than ±5%, but the viscosity change rate after storage for 4 weeks was ±5% or more.
B: The viscosity change rate after storage for 2 weeks was less than ±5%, but the viscosity change rate after storage for 3 weeks was ±5% or more.
C: Viscosity change rate after storage for 1 week was less than ±5%, but viscosity change rate after storage for 2 weeks was ±5% or more.
D: The rate of change in viscosity after storage for 1 week was ±5% or more.

<Preparation example of film substrate to which pretreatment liquid is applied>
About the pre-treatment liquid manufactured above, K control coater K202 by Matsuo Sangyo Co., Ltd., wire bar No. 0, the pretreatment liquid prepared above was applied to the following base material with a wet film thickness of 4.0 ± 0.2 μm, and then placed in an air oven at 60 ° C. and dried for 30 seconds. A base material was produced.

<Film substrate used for evaluation (impermeable substrate)>
・OK top coat: Coated paper manufactured by Oji Paper Co., Ltd. 4.5 g / m ²
・ PET: Futamura polyethylene terephthalate film “FE2001” (thickness 12 μm)

<Evaluation of coating unevenness of pretreatment liquid>
Based on the above method, the appearance of the pretreatment liquid applied to the substrate was observed visually and with a magnifying glass. The evaluation criteria are as follows, and AA and A are defined as the practically usable regions.
AA: No cissing or coating unevenness was observed visually or with a magnifying glass.
A: Coating unevenness was slightly observed with a magnifying glass, but no repelling or coating unevenness was visually observed. No unevenness was observed C: Repellency or coating unevenness was visually observed

Examples 1 to 14 are pretreatment liquids using suitable water-soluble cationic resins, which have high storage stability and can provide excellent printed matter with no coating unevenness of the pretreatment liquid. It was possible.

Comparative Example 1 shows that the water-soluble cationic resin (C) does not have a maximum molecular weight of 100 to 5,000 in gel permeation chromatography measurement. In addition, since the area ratio of the elution curve was 100/0, the storage stability was lowered.
Further, in Comparative Example 2, the area ratio of the elution curve was 70/30, which resulted in coating unevenness due to the large amount of low-molecular-weight components.
In Comparative Example 3, the weight-average molecular weight of the entire water-soluble cationic resin (C) was less than 50,000, resulting in uneven coating.
In Comparative Example 4, the total weight average molecular weight of the water-soluble cationic resin (C) was greater than 200,000, resulting in deterioration of storage stability and coating unevenness.
In Comparative Example 5, the area ratio of the elution curve was 70/30, which resulted in lower storage stability and uneven coating on the PET substrate due to a large amount of low-molecular-weight components.

<Production of water-based inkjet ink>
<Production Example of Pigment Dispersion Resin D-1>
A reaction vessel equipped with a gas inlet tube, a thermometer, a condenser and a stirrer was charged with 95 parts of butanol and purged with nitrogen gas. The inside of the reaction vessel was heated to 110° C., and a mixture of 35 parts of styrene as polymerizable monomers, 35 parts of acrylic acid, 30 parts of lauryl methacrylate, and 6 parts of V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) as a polymerization initiator was added. It was added dropwise over 2 hours to carry out a polymerization reaction. After the completion of dropping, the mixture was reacted at 110° C. for 3 hours, then 0.6 parts of V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) was added, and the reaction was further continued at 110° C. for 1 hour to form a solution of pigment dispersion resin D-1. got Further, after cooling to room temperature, dimethylaminoethanol was added to completely neutralize the mixture, and then 100 parts of water was added to make it aqueous. Thereafter, the butanol is heated to 100° C. or more to azeotrope with water to distill off the butanol, and the solid content is adjusted to 30%, thereby obtaining an aqueous solution of the pigment dispersion resin D-1 (solid content 30%) was obtained. The pigment dispersion resin D-1 had an acid value of 272 mgKOH/g and a weight average molecular weight of 28,000, which were measured by the methods described above.

<Production Examples of Pigment Dispersion Resins D-2 to D-6>
As shown in Table 5 below, the aqueous solutions of pigment dispersion resins D-2 to D-6 (solid content 30%) was obtained.

<Production Examples of Pigment Dispersions 1C, 1M, 1Y, and 1K>
20 parts of LIONOLBLUE 7358G (C.I. Pigment Blue 15:3) manufactured by Toyocolor Co., Ltd., 20 parts of aqueous solution of pigment dispersion resin D-1 (solid content 30%), and 60 parts of water are mixed and pressed with a stirrer. After mixing, main dispersion was carried out using a Dyno mill with a volume of 0.6 L filled with 1800 g of zirconia beads with a diameter of 0.5 mm to obtain a pigment dispersion liquid 1C. In addition, the above C. I. Pigment Dispersions 1M, 1Y, and 1K were obtained in the same manner as Pigment Dispersion 1C, except that Pigment Blue 15:3 was replaced with the pigments shown below.
・Magenta: FASTGENSUPERMAGENTARG manufactured by DIC (C.I. Pigment Red 122)
・Yellow: LIONOLYELLLOWTT1405G (C.I. Pigment Yellow 14) manufactured by Toyo Color Co., Ltd.
・Black: Print X85 (carbon black) manufactured by Orion Engineered Carbons

<Production Examples of Pigment Dispersions 2 to 6 (C, M, Y, K)>
Pigment dispersions 1C, 1M, 1Y, and 1K are used in the same manner as pigment dispersions 1C, 1M, 1Y, and 1K, except that pigment dispersion resin D-1 is replaced with aqueous solutions of pigment dispersion resins D-2 to 6 (solid content: 30%). to obtain pigment dispersions 2 to 6 (C, M, Y, K, respectively).

<Production Example of Pigment Dispersion 1W>
40 parts of Typaque CR-90-2 (titanium oxide) manufactured by Ishihara Sangyo Co., Ltd., 20 parts of aqueous solution (solid content 30%) of pigment dispersion resin 1, and 40 parts of water are mixed and premixed with a stirrer, Main dispersion was carried out using a Dyno mill with a volume of 0.6 L filled with 1800 g of zirconia beads with a diameter of 0.5 mm to obtain a pigment dispersion liquid 1W (pigment concentration: 40%).

<Production Examples of Pigment Dispersions 2W to 6W>
Pigment dispersions 2W to 6W were obtained in the same manner as for pigment dispersion 1W, except that pigment dispersion resin 1 was replaced with an aqueous solution (solid content: 30%) of pigment dispersion resins 2 to 6. rice field.

<Manufacturing example of water-based inkjet ink set S-1 (CMYKW)>
The following materials were sequentially put into a mixing vessel equipped with a stirrer and stirred until sufficiently uniform. After that, filtration was performed with a membrane filter having a pore size of 1 μm to remove coarse particles that cause clogging of the inkjet head, thereby obtaining water-based inkjet cyan ink 1 . By using pigment dispersions 1M, 1Y, 1K, and 1W instead of pigment dispersion 1C, cyan (C), magenta (M), yellow (Y), black (K), and white (W) can be obtained. A set S-1 of aqueous inkjet inks consisting of colors was obtained.
・Pigment dispersion 1C 25 parts ・Joncryl 8211 (solid content 44%) 15 parts ・1,2-propanediol (1,2-PD) 20 parts ・Surfinol 465 (solid content 100%) 1 part ・Proxel GXL (Solid content 100%) 0.05 parts Ion-exchanged water 38.95 parts

In the above production examples, Joncryl 8211 is an acrylic resin emulsion (MFT 57° C., solid content 44%) manufactured by BASF.

<Manufacturing example of water-based inkjet ink sets S-2 to 6 (CMYKW)>
Five inks of cyan (C), magenta (M), yellow (Y), black (K) and white (W) were prepared in the same manner as in the water-based inkjet ink set S-1 except that the materials listed in Table 6 below were used. A set of water-based inkjet inks S-2-6 consisting of colors was obtained.

<Example of making printed matter>
An inkjet head KJ4B-QA (manufactured by Kyocera Corporation, design resolution 600 dpi) is installed on the upper part of the conveyor that can convey the base material, and the set of water-based inkjet inks produced above is applied from the upstream side to K, C, M, Y, W filled in order. Next, after fixing the film substrate to which the pretreatment liquid was applied, which was produced above, on the conveyor, the conveyor was driven at a constant speed, and the inkjet ink was applied when passing through the installation portion of the inkjet head. Each droplet was ejected at a drop volume of 10 pL, and the following images were printed. Immediately after printing, the printed material was placed in an air oven at 70° C. and dried for 5 minutes to prepare a printed material.

The conveyor driving speed was set to 30 m/min or 50 m/min, and printing was performed under each condition. In addition, as a print image, a solid patch of 5 cm × 5 cm with a print rate of 100% is adjacent in the order of CMYK (hereinafter referred to as a “solid patch image”), and the total print rate (sum of the print rate of each color) is 40 to 320. % (hereinafter referred to as a "gradation image". Note that the printing rate of each color is the same for each total printing rate). A printed matter was produced.

[Examples 15 to 33, Comparative Examples 6 to 10]
The printed material was produced using the combination of the pretreatment liquid and water-based inkjet ink set shown in Table 7. As the base material, PET: polyethylene terephthalate film "FE2001" (thickness: 12 μm) manufactured by Futamura Co., Ltd. and OK topcoat: 4.5 g/m ² coated paper manufactured by Oji Paper Co., Ltd. were used.
Using this printed matter or the pretreatment liquid itself, the following evaluations 1 to 5 were performed. Table 7 shows the evaluation results.

<Evaluation 1: Evaluation of mixed color bleeding>
Printing is performed under the above conditions, a gradation image print is produced on the film base material coated with the pretreatment liquid, and the dot shape of the printed portion is observed at 400 times using an optical microscope to evaluate color mixture bleeding. gone. The evaluation criteria are as follows, and the S, AA, and A evaluations are defined as the practical usable range.
S: The dots in the 4-color printed portion were independent at any printing rate, and no mixed color bleeding was observed. AA: The dots in the 4-color printed portion were independent at a printing rate of 40 to 300%, and mixed color bleeding was observed. was not observed, but mixed-color bleeding was observed in the printed area with a printing rate exceeding 300%. At any printing rate, the dots in the four-color printed area were independent, and no mixed-color bleeding was observed. A: Printing The dots in the 4-color printed portion with a printing rate of 40 to 280% were independent, and no mixed color bleeding was observed, but mixed color bleeding was observed in the printed portion with a printing rate of more than 280% B: Printing rate of 40 to 240% The dots in the 4-color printed portion were independent, and color mixture bleeding was not observed.
C: Mixed color bleeding was clearly seen in the 4-color printed portion with a printing rate of 40 to 240%

<Evaluation 2: Evaluation of color unevenness>
Printing was performed under the same conditions as in Evaluation 1 above, and a gradation image print was produced on the film substrate coated with the pretreatment liquid, and the degree of color unevenness in the four-color (CMYK) print was visually observed. An evaluation of unevenness was performed. The evaluation criteria are as follows, and the S, AA, and A evaluations are defined as the practical usable range.
S: The dots in the 4-color printed portion were independent at any printing rate, and no color unevenness was observed AA: The dots in the 4-color printed portion were independent at a printing rate of 40 to 300%, and color unevenness was not observed, but mixed color bleeding was observed in the printed part with a printing rate of more than 300%. Color unevenness was seen in the printed part exceeding B: No color unevenness was seen in the four-color printed part with a printing rate of 40 to 240%, but color unevenness was seen in the printed part with a printing rate of more than 240% C: Color unevenness was clearly seen in the 4-color printing part with a printing rate of 40 to 240%.

<Evaluation 3: Evaluation of dryness>
Based on the method described above, a four-color solid patch image print was used on a PET film substrate to which the pretreatment liquid had been applied, under the condition of a conveyor driving speed of 50 m/min. Immediately after printing, the printed matter was placed in an air oven at 70° C., and then the printed matter was taken out from the air oven every minute, and the dryness was evaluated by visually observing the state of rubbing the surface with a finger. The evaluation criteria are as follows, and AA, A, and B are defined as practically usable regions.
AA: The printed material was dried 1 minute after the air oven was turned on, and the ink did not adhere even when rubbed with a finger. No adhesion B: The ink adhered to the finger 2 minutes after the air oven was turned on, but did not adhere 3 minutes later C: The ink adhered to the finger even after 3 minutes from the air oven turned on

<Evaluation 4: Evaluation of adhesion>
Based on the method described above, a four-color solid patch image print was used on a PET film substrate to which the pretreatment liquid had been applied, under the condition of a conveyor driving speed of 50 m/min. A cellophane tape (18 mm wide) manufactured by Nichiban Co., Ltd. was firmly adhered to the surface of the printed image, and then held at the tip of the cellophane tape and peeled off while maintaining an angle of 90 degrees. The adhesiveness was evaluated by visually checking the surface of the printed matter and the surface of the cellophane tape after peeling off. The evaluation criteria are as follows, and AA, A, and B are defined as practically usable regions.
AA: The peeling area to the adhesion surface of the cellophane tape was less than 5% A: The peeling area to the adhesion surface of the cellophane tape was 5% or more and less than 10% B: The peeling area to the adhesion surface of the cellophane tape was 10% It was less than 20% C: The peeling area with respect to the adhesion surface of the cellophane tape was 20% or more and less than 30% D: The peeling area with respect to the adhesion surface of the cellophane tape was 30% or more

<Evaluation 5: Laminate strength (adhesive strength)>
Using a test coater, on the following film base material coated with a pretreatment liquid, solid printing with a single color printing rate of 100% and solid printing with a total printing rate of 200% for two colors. The following laminate adhesive was applied under conditions of a temperature of 60° C. and a coating speed of 50 m/min (application amount: 2 g/m ² ). When the lamination adhesive contained a solvent component, the solvent component was dried after coating, and the coating was applied so that the coating amount after drying was 2 g/m ² . Furthermore, after superimposing the following sealant film on the coated surface of the laminate adhesive, the laminate adhesive composition is cured by aging for 1 day in an environment of 40 ° C. and 80% RH, and laminated lamination made the body.
<Film substrate>
・Futamura polyethylene terephthalate film “FE2001” (thickness 12 μm)
<Sealant film>
・ Linear low-density polyethylene film “TUX-FC-D” manufactured by Mitsui Chemicals Tohcello (thickness 40 μm)
<Lamination adhesive>
・TM-265L/CAT-RT37 manufactured by Toyo-Morton Co., Ltd. (solvent lamination adhesive)

A test piece was cut from the laminated laminate to a length of 300 mm and a width of 15 mm. Using an Instron type tensile tester, the film was pulled at a peel speed of 300 mm/min in an environment of 25° C., and the T-peel strength (N) between the film substrate and the sealant film was measured. This test was performed 5 times and the average value was obtained to evaluate the adhesive strength. The evaluation criteria are as follows, and the S, AA, and A evaluations are defined as the practical usable range.
S: Adhesive strength 2.0 N or more AA: Adhesive strength 1.5 N or more and less than 2.0 N A: Adhesive strength 0.6 N or more and less than 1.5 N B: Adhesive strength 0.3 N or more and less than 0.6 N C: Adhesion Force less than 0.3N

<Evaluation 6: Adhesive strength after heat sterilization>
Two laminated laminates were superimposed with the sealant film on the inside, and sealed with a heat sealer under the conditions of 150° C., 2 kg/cm ² , and 1 second to prepare a tare. Using this, hot water sterilization was performed at 95° C. for 30 minutes using a high-temperature and high-pressure cooking sterilization tester “RCS-40RTGN” manufactured by Nissaka Seisakusho. After the treatment, the laminate strength was evaluated in the same manner as described above.

<Evaluation 7: Evaluation of Appearance>
Appearance was evaluated by visually observing the laminate test piece used in the adhesive strength evaluation after heat sterilization from the film substrate side. The evaluation criteria are as follows, and the AA and A evaluations are the practically usable areas.
AA: The laminate has no delamination and foaming, or has delamination and foaming in an area of less than 3% A: The laminate has delamination and foaming in an area of 3% or more and less than 20% B : The laminate has delamination and bubbles in an area of 20% or more and less than 50% C: The laminate has delamination and bubbles in an area of 50% or more

In Examples 14 to 31, since a system using a water-soluble cationic resin suitable for the pretreatment liquid was used, it was possible to obtain prints with excellent image quality without color mixture bleeding or color unevenness. In addition, it was possible to obtain a four-color solid image print with good drying properties and good adhesion of the ink surface to the base material. Furthermore, even after laminating the printed material and treating with hydrothermal bacteria, good adhesive strength was maintained, and all of them were practically usable. In particular, when comparing Examples 15 to 27 and Example 28 in the evaluation of mixed color bleeding of printed matter for an OK topcoat substrate, the structure derived from the cationic vinyl monomer (c1) represented by the general formula (1) It was found that having a unit exhibits a higher effect of suppressing color mixture bleeding.

On the other hand, in Comparative Example 8, since the total weight average molecular weight of the water-soluble cationic resin (C) is less than 50,000, the ink-jet ink setting property for the PET substrate is insufficient, resulting in mixed color bleeding. As a result, the appearance after the heat sterilization treatment was inferior. In Comparative Example 6, the area ratio of the elution curve of the entire gel permeation chromatography of the water-soluble cationic resin (C) was 100/0 in terms of H/L. there is Therefore, it is thought that when the four colors of K, C, M, and Y were printed in this order, the cohesive force was insufficient, and mixed color bleeding and color unevenness occurred in the inkjet ink set. The total weight-average molecular weight of the water-soluble cationic resin (C) was 200,000 or more, resulting in color unevenness in the inkjet ink set on the OK topcoat and the PET substrate.

From these results, a water-soluble cationic resin (C) containing a high molecular weight component (H) and a low molecular weight component (L) within a certain ratio range and having an overall weight average molecular weight within a predetermined range is used. Thus, it is possible to obtain a pretreatment liquid with high storage stability and a coated article with no coating film unevenness. Furthermore, it was clarified from the printed matter evaluation that it is effective in improving mixed color bleeding and color unevenness of the inkjet ink set. Furthermore, a printed matter having excellent lamination strength after hot water sterilization could be obtained.

Claims (7)

A pretreatment liquid for one-pass printer type inkjet printing,
containing resin fine particles (A), a flocculant (B), and water,
The flocculant (B) contains a water-soluble cationic resin (C) having a structural unit derived from a vinyl monomer (c1) having a cationic group,
A pretreatment liquid that satisfies the following (1) and (2) in an elution curve when the entire water-soluble cation resin (C) is measured by gel permeation chromatography.
(1) Having a high molecular weight component (H) having a maximum value at a molecular weight of 5000 or more with a molecular weight of 5000 as a boundary and a low molecular weight component (L) having a maximum value at a molecular weight of 100 to 5000, and having the molecular weight of 5000 as a boundary , the area ratio of the elution curves of the high molecular weight component (H) and the low molecular weight component (L) is H/L = 75/25 to 97/3; (2) the weight average molecular weight is 50,000 to 200; , 000 2. The pretreatment liquid according to claim 1, wherein the vinyl monomer (c1) having a cationic group has a structure represented by the following general formula (1).
General formula (1)

(In general formula (1), R ¹ represents a hydrogen atom or a methyl group, Z represents an oxygen atom, -NH-, or -O-CH ₂ -NH-C(=O)O-. R ² , R ³ and R ⁴ each independently represent a methyl group, an ethyl group or a propyl group, which may be the same or different, and ^{X −} represents a halide ion, a sulfonate anion or an alkylsulfonate anion. , represents an acetate anion or an alkylcarboxylate anion. n represents an integer of 2 to 6.) 3. The pretreatment liquid according to claim 1, wherein the content of the water-soluble cationic resin (C) is 60 to 200 parts by mass based on 100 parts by mass of the fine resin particles (A). The pretreatment liquid according to any one of claims 1 to 3, wherein the resin fine particles (A) have a glass transition temperature of -50 to 50°C. The pretreatment liquid according to any one of claims 1 to 4, which is for inkjet printing on impermeable substrates. An aqueous inkjet ink set comprising the pretreatment liquid according to any one of claims 1 to 5 and one or more aqueous inkjet inks,
An aqueous inkjet ink set in which at least one of the aqueous inkjet inks contains a pigment (P), a pigment dispersion resin (D), and water. A method for producing a printed matter, comprising printing the water-based inkjet ink set according to claim 6 on an impermeable substrate,
a step of printing a pretreatment liquid on the impermeable base material in an amount such that the film thickness after drying is 0.1 to 1.6 μm;
a step of printing a water-based inkjet ink on the portion of the impermeable substrate printed with the pretreatment liquid by inkjet printing using a one-pass printer method;
and drying the impermeable substrate printed with the water-based inkjet ink.