JP6541088B1 - Pretreatment liquid, and ink set including the pretreatment liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a printed matter excellent in image quality free from color mixing blur and color unevenness, having no coating defects such as coating unevenness and repelling on a non-permeable base material such as a film base material. To provide a pretreatment liquid excellent in adhesion to the non-permeable substrate and also in long-term storage stability, and also excellent in drying property during printing and blocking resistance of printed matter. It is providing a process liquid. A pretreatment liquid used with an aqueous inkjet ink containing a pigment and water, wherein the pretreatment liquid comprises resin particles (A), a coagulant (B), and a thickener (C). Pretreatment liquid containing surfactant (D) and water. 【Selection chart】 None

Description

The present invention relates to a pretreatment liquid, an ink set containing the pretreatment liquid, and a printed material produced using the ink set.

Unlike conventional plate printing such as offset printing, digital printing does not require a plate-making film or plate making, so that cost reduction and speeding up can be realized, and it is expected to be widely spread in the future.

In the ink jet printing method, which is a type of digital printing, ink droplets are directly ejected from a very fine nozzle onto a printing substrate and adhered to obtain characters and images. The inkjet printing method has advantages such as low noise of the device to be used, good operability, and easy colorization, and is widely used as an output device in offices and homes. In addition, with the improvement of the inkjet technology, it is beginning to be used as a digital printing output machine also in industrial applications.

Conventionally, the ink used by the inkjet printing system in industrial use was solvent ink and UV ink. However, in recent years, the demand for water-based inks has increased in terms of environmental issues.

The aqueous ink used in the inkjet printing method (hereinafter, also simply referred to as "inkjet") has conventionally been intended for plain paper and special-purpose paper (for example, photographic glossy paper). That is, in addition to water as a main component, a water-soluble organic solvent such as glycerin or glycol is added to control the wettability to the substrate and the drying property. When a pattern of characters or an image is printed on the above-mentioned base material using an inkjet aqueous ink (hereinafter also referred to as “aqueous inkjet ink”, “aqueous ink” or simply “ink”) composed of these liquid components, The liquid component penetrates into the substrate to dry and settle.

On the other hand, the base material for inkjet includes not only the above-mentioned plain paper or special paper, or high permeability paper such as high quality paper or recycled paper, but also low such as coated paper, art paper, and fine coated paper. There are also permeable ones and non-permeable ones such as film substrates. Up to now, practicable image quality has been realized using a water-based inkjet ink as described above for highly permeable substrates and low-permeable substrates. On the other hand, for a non-permeable substrate such as a film substrate, the ink droplets after landing do not penetrate into the substrate at all, so that the drying by the permeation hardly occurs, resulting in the liquid The drops were united to cause bleeding and unevenness, and the image quality was impaired.

In addition, since the ink does not penetrate at all in the non-permeable substrate, it is difficult to obtain sufficient adhesion. If the adhesion to the non-permeable substrate is insufficient, the printed layer (ink film) is easily peeled off by rubbing, which causes a practical problem.

As a measure for the above problems, application treatment of a pretreatment liquid to a non-permeable substrate is known. Generally, as a pretreatment liquid for aqueous inkjet ink, a layer (ink receiving layer) for absorbing the liquid component in the aqueous inkjet ink and improving the drying property (see Patent Documents 1 and 2), and a solid component Forming a layer (ink aggregation layer) for preventing bleeding and color unevenness between aqueous ink jet ink droplets by intentionally causing aggregation of ink and thickening of ink (see Patent Documents 3 to 4) ) Are known.

However, in the case of the ink receiving layer, for example, when receiving a large amount of ink at one time, the image may be warped due to the swelling of the ink receiving layer, bleeding or color unevenness due to exceeding an acceptable amount, or ink components to the receiving layer. Concentration reduction due to absorption may occur. Moreover, when forming a receptive layer, it is necessary to make the coating film thickness of a pre-processing liquid thicker than the case of the ink aggregation layer mentioned later. When the coating amount is large, the drying property of the pretreatment liquid itself is reduced, and there is a concern that defects such as drying defects may occur. As described above, when used as a non-permeable substrate such as a film substrate, the above-mentioned problems are considered to easily occur because the pretreatment liquid does not penetrate at all.

On the other hand, as an example of a pretreatment liquid for forming an ink aggregation layer, Patent Document 3 describes a pretreatment liquid containing a colorant flocculant such as an organic acid, polyolefin particles, and an aqueous organic solvent, By using the pretreatment liquid, it is supposed that a printed matter with excellent thin line reproducibility can be obtained.
However, what is focused on in the above Patent Document 3 is a highly permeable substrate, and there is no specific description on a non-permeable substrate such as a film. Although the present inventors actually tried to use the pretreatment solution described in Patent Document 3 for a polyolefin film or nylon film, the adhesion to the film is insufficient, and the print layer is easily peeled off. The

Patent Document 4 also describes that, by using a treatment liquid containing an aggregating agent and a betaine compound, a printed material having excellent image quality can be obtained while curling is suppressed. However, plain paper is used in the evaluation of image quality (solid uniformity) in the example of Patent Document 4, and there is no specific description on a non-permeable substrate such as a film. In fact, when the present inventors evaluated the pretreatment liquid described in Patent Document 4 using the above-mentioned film, coating unevenness occurred on the film, and after coating of the pretreatment liquid, When an aqueous inkjet ink was printed, it resulted in a print inferior in image quality.

Further, Patent Document 5 discloses a reaction liquid (treatment liquid) containing an associative thickener having a urethane bond or an ester bond and a reaction agent (flocculant), and is excellent in marker resistance and optical density. Printed materials are obtained. Patent Document 6 discloses an inkjet film substrate having a coating layer containing an aqueous latex resin, a coagulant, and a thickener.
It is described that the printed matter is prevented from being cracked and a printed matter excellent in image quality can be obtained.
However, although the details will be described in Examples, when the present inventors evaluated the pretreatment solution described in Patent Documents 5 and 6 using the film, coating unevenness (film thickness on the film) was observed. In addition to the occurrence of coating defects such as unevenness of the coated surface due to non-uniformity of the coating surface and repelling (exposure of the substrate surface seen on a part of the coated surface), the printed matter is inferior in image quality and adhesion. Oops.

It is also known that a pre-treatment liquid using a resin such as a polyurethane resin, a polyolefin resin, or a polyester resin imparts an adhesion function. However, if the above-mentioned resin and coagulant are simply used in combination to achieve both adhesion and image quality, it becomes a pretreatment liquid which is inferior in long-term storage stability, and the compatibility between both is poor. There is a risk that the occurrence of unevenness during coating or drying and the deterioration of image quality may occur.

JP-A-6-297830 JP, 2000-335084, A Unexamined-Japanese-Patent No. 2016-168782 JP, 2016-68306, A Unexamined-Japanese-Patent No. 2018-1625 JP, 2017-109411, A

The present invention has been made to solve the above-mentioned problems, and the object thereof is that there is no coating defect such as coating unevenness or repelling on a non-permeable substrate such as a film substrate, and the color mixture blur or color It is an object of the present invention to provide a pre-treatment liquid which can obtain a printed matter excellent in image quality without unevenness and which is also excellent in adhesion to the non-penetrable substrate and long-term storage stability. Another object of the present invention is, in addition to the above, to provide a pretreatment liquid which is also excellent in the drying property during printing and the blocking resistance of printed matter. Another object of the present invention is to provide an ink set comprising the above pretreatment liquid and an aqueous inkjet ink, which can suitably exhibit the above-mentioned characteristics, and a printed material produced using the ink set.

That is, the present invention is a pretreatment liquid used with an aqueous inkjet ink containing a pigment and water,
The pretreatment liquid comprises resin particles (A), a coagulant (B), a thickener (C) and a surfactant (D).
) And water,
The 50% particle diameter (D50) of the resin particles (A) is 30 to 350 nm,
The coagulant (B) contains at least one selected from the group consisting of polyvalent metal salts and cationic polymer compounds,
The moisture absorption rate at 80% relative humidity of the coagulant (B) is 75% by mass or less,
The thickener (C) contains a hydrophobically modified water-soluble urethane resin,
The present invention relates to a pretreatment solution in which the HLB value of the surfactant (D) is 13.5 or less.

The present invention also relates to the above pretreatment liquid, wherein the resin particles (A) are polyolefin resin particles.

The present invention also relates to the above pretreatment liquid, wherein the HLB value of the surfactant (D) is 1.0 to 8.5.

The present invention also relates to the above pretreatment liquid, wherein the coagulant (B) contains a divalent metal salt as the polyvalent metal salt.

In the present invention, the compounding amount of the thickener (C) is 1 with respect to the compounding amount of the resin particles (A).
It relates to the above-mentioned pretreatment liquid which is -100 mass%.

The present invention also relates to the above pretreatment liquid, which further comprises a water-soluble organic solvent having a static surface tension of 20 to 40 mN / m at 25 ° C.

Further, the present invention provides the above-mentioned pretreatment liquid,
An ink set comprising a pigment, a water soluble organic solvent, and an aqueous inkjet ink comprising water.

The present invention also relates to a printed matter obtained by printing the aqueous inkjet ink on a substrate to which the above-mentioned pretreatment liquid has been applied.

According to the present invention, a non-permeable substrate such as a film substrate can be provided with a coating defect free from coating defects such as coating unevenness and repelling, and excellent in image quality free from color mixing blur and color unevenness, and It is possible to provide a pretreatment liquid which is excellent in adhesion to the non-permeable substrate and long-term storage stability. In addition to the above, it is possible to provide a pretreatment liquid which is also excellent in the drying property during printing and the blocking resistance of printed matter. Furthermore, it is possible to provide an ink set comprising the pretreatment liquid and an aqueous inkjet ink, which can suitably exhibit the above-mentioned properties, and a printed material produced using the ink set.

Hereinafter, the pretreatment liquid, which is an embodiment of the present invention (hereinafter, also simply referred to as “the present embodiment”), will be described by raising a preferred embodiment.

As described above, the pretreatment liquid using a resin (binder resin) used to impart adhesion to a non-permeable substrate in combination with a coagulant used to improve the image quality is
Storage stability and adhesion deteriorate compared to when each is used alone. Furthermore, when coating on a film or drying, unevenness or repellence may occur on the coated surface, and when the aqueous inkjet ink is printed thereon, the image quality may also be deteriorated.

Adhesion by the binder resin is manifested by the formation of hydrogen bonds and intermolecular interactions on the surface of the impermeable substrate. On the other hand, the improvement of the image quality by the coagulant is caused by the fact that the cation component generated by the ionization of the coagulant acts on the solid component (pigment or resin component) in the aqueous inkjet ink to cause aggregation or increase of the solid component. By causing the viscosity, to suppress the color bleeding and color unevenness on the non-permeable substrate.

However, when the binder resin and the coagulant are used in combination, an interaction between the two occurs, which may reduce the solubility and dispersion stability of the binder resin, and as a result, the stability over a long period of time It becomes difficult to maintain. Further, it is considered that the compatibility state between the binder resin and the aggregating agent in the pretreatment liquid tends to be uneven due to the influence of the interaction. In particular,
At the time of drying of the pretreatment liquid, that is, when the liquid component in the pretreatment liquid is volatilized and concentrated, the ionizing state of the flocculant changes, so the binder resin and the flocculant are formed on the impermeable substrate. It is thought that it distributes unevenly and, as a result, coating unevenness tends to occur on the non-permeable substrate. Further, due to the occurrence of the nonuniformity, the adhesion is degraded by making the hydrogen bond and the intermolecular interaction formed between the binder resin and the impermeable substrate nonuniform as well. Furthermore, when the aqueous inkjet ink is printed later because of the uneven distribution of the coagulant and the coating unevenness, the aggregation and thickening unevenness of the aqueous inkjet ink droplets and the flow on the coated surface It is thought that color mixing blur and color unevenness occur.

Then, as a result that the present inventors continued earnestly examining in order to solve said subject, resin particles (A) which have a particle size of a specific range as binder resin, and a coagulant | flocculant which has a specific moisture absorption rate (B)
), A thickener (C) containing a hydrophobically-modified water-soluble urethane resin, and a surfactant (D) having an HLB value in a specific range in combination for coating on a non-permeable substrate There is no coating defect such as unevenness and repelling, and it is possible to obtain a printed matter excellent in image quality without mixed bleeding and color unevenness, and also excellent in adhesion to the non-permeable substrate and long-term storage stability. It was found to be a pretreatment solution. Although the details of the mechanism which can solve the above-mentioned subject suitably with the pretreatment liquid of the above-mentioned composition are unknown, the present inventors presume as follows.

First, the pretreatment liquid of the present embodiment contains resin particles (A). Generally, there are two types of resin, water-soluble resin and resin particles, which can be used properly depending on the characteristics required for the pretreatment liquid and the printed matter. In the case of the pretreatment liquid of the present embodiment, resin particles are used as a binder resin because it is necessary to form an association state with a hydrophobically modified water-soluble urethane resin described later. Also, since resin particles can be blended with a larger amount of resin than in the case of water-soluble resin,
It is also a suitable material from the viewpoint of enhancing the adhesion, abrasion resistance and water resistance of the printed matter.

The flocculant (B) contained in the pretreatment liquid of the present embodiment contains at least one selected from the group consisting of polyvalent metal salts and cationic polymer compounds, and has a temperature of 40 ° C. and a relative humidity of 80%.
The moisture absorption rate in is less than 75% by mass. The polyvalent metal salt and the cationic polymer compound which function as the aggregating agent (B) are present as ions in the pretreatment liquid. In general, the more easily a compound is ionized in liquid, the more the dissociation constant (when the aggregating agent (B) is a polyvalent metal salt,
(Also called “ionization constant”) is high. And as the compound having a larger dissociation constant or ionization constant, the solubility in water tends to be higher and the moisture absorption rate also tends to be higher. However, when the moisture absorption rate of the coagulant (B) is too high, the adhesiveness and the drying property are deteriorated by absorbing the moisture in the air. Therefore, in the present embodiment, as described above, the above-described deterioration of the quality is suppressed by defining the moisture absorption rate of the coagulant (B). Further, by suppressing the moisture absorption of water, it is considered that the pretreatment liquid does not dry unevenly at the time of drying, and it is possible to realize further suppression of coating unevenness.

Furthermore, the pretreatment liquid of the present embodiment contains a hydrophobically modified water-soluble urethane resin as a thickener (C). The hydrophobic groups present in the water-soluble urethane resin molecule interact with the resin particles to form an association state. As a result, a pretreatment liquid having suitable visco-elastic properties is obtained, and
It is possible to form a uniform coating film with excellent adhesion and no coating unevenness by thickening quickly when drying and suppressing non-uniformity and separation between the resin particles (A) and the coagulant (B). it is conceivable that. In addition to the formation of the association state, the presence of the thickener (C) to protect the resin particles (A) is considered to improve the chemical stability of the resin particles (A). As a result, the interaction with the coagulant (B) is suppressed, and the improvement of the storage stability as the pretreatment liquid can be realized.

In addition, as a result of continuous investigations by the present inventor, the 50% particle diameter of the resin particles (A) is 30 to 3
When it is 50 nm, it has been found that the above effect is particularly improved. The visco-elastic properties of the pretreatment liquid and the stabilization effect of the flocculant (B) can be obtained by optimizing the amount of the thickener (C) associated with the resin particles (A) having the above particle diameter, although the details are unknown. Not only improves the viscosity but also
Is considered to be able to suppress the influence of the

In addition, in the case of the pre-processing liquid which contains a coagulant (B) and a thickener (C), but does not contain a resin particle (A), the association state by the said thickener (C) is not formed as mentioned above. Although the viscosity of the pretreatment solution can be increased by adding a large amount of the thickener (C), when the present inventors examined using such pretreatment solution, coating unevenness was observed. Could not prevent. It is considered that the state of association affects not only the viscosity but also the elasticity that affects the state at the time of coating.

Moreover, the pretreatment liquid of this embodiment contains surfactant (D) whose HLB value is 13.5 or less. In general, a non-permeable substrate such as a film has a low surface free energy of the substrate itself, and in order to uniformly apply the pretreatment liquid, a surfactant is used to impart wettability to the pretreatment liquid. You need to However, depending on the type of surfactant, repellence may occur due to the high level of bubbles and interfacial orientation, and the destruction of the association state and the deterioration of the stabilizing effect of the coagulant (B) may be caused. There is a fear.

Then, as a result of the present inventors continuing earnest examination, by using surfactant (D) which has the said HLB value with resin particle (A), a coagulant (B), and a thickener (C), It has been found that uniform coating on a non-permeable substrate and further improvement of the image quality can be realized without deteriorating the above effects. Although the details are also unknown, it is considered that the surfactant (D) having a suitable HLB value is incorporated into and compatibilized in the association state formed by the thickener (C).

As described above, it is possible to obtain a printed matter excellent in image quality free from coating defects such as coating unevenness and repelling and having no mixed bleeding or color unevenness with respect to the non-permeable substrate, and the above-mentioned non-penetration In order to obtain a pretreatment liquid excellent in adhesion to a substrate and long-term storage stability, it is essential to adopt the above-mentioned constitution.

  Then, below, each component which comprises the pre-processing liquid of this embodiment is demonstrated in detail.

<Resin particles (A)>
The pretreatment liquid of the present embodiment contains resin particles (A) as a binder resin. The "resin particle" in this specification refers to that whose particle diameter measured by the method mentioned later is 5-1000 nm.

As described above, the 50% particle diameter (D50) of the resin particles (A) is 30 to 350 nm.
In addition, long-term storage stability is ensured by the adhesion to the non-permeable substrate and the association formed with the thickener (C), and coating unevenness during coating and drying is suppressed, and image quality is improved. From the viewpoint of obtaining excellent printed matter, it is more preferably 50 to 350 nm, particularly preferably 5
It is 0-280 nm. The 50% particle diameter (D50) of the resin particles (A) was measured by a dynamic light scattering method using a particle size distribution analyzer (for example, Microtrack UPAEX-150 manufactured by Microtrack Bell Inc.), based on volume Cumulative 50% diameter value (median diameter) at

The type of resin particles (A) that can be used for the pretreatment liquid of the present embodiment is not particularly limited, and polyurethane resin, polyurea resin, polyurethane urea resin, (meth) acrylic resin, acrylic modified polyurethane resin, styrene- (Meth) acrylic resin, styrene-(
Anhydride) maleic acid resin, rosin modified maleic acid resin, polyolefin resin, polyester resin, polyether resin, polycarbonate resin, etc. can be exemplified. Among the above, from the viewpoint of adhesion to the non-permeable substrate, one or more selected from polyurethane resin, polyurethane polyurea resin, (meth) acrylic resin, acrylic modified polyurethane resin, and polyolefin resin is more preferable. Furthermore, depending on the association formed with the thickener (C),
It is particularly preferable to use a polyolefin resin as the resin particle (A) from the viewpoint of securing long-term storage stability and suppressing coating unevenness at the time of coating and drying. In the present specification, “(meth) acrylic” means acrylic and / or methacrylic and “(
Anhydride) "maleic acid" means maleic acid and / or maleic anhydride.

In addition, ethylene, propylene, as an olefin which comprises the said polyolefin resin.
One or more selected from butenes can be suitably used, and it is particularly preferable to contain at least propylene.

Moreover, non-modified polyolefin resin, halogenated polyolefin resin, modified polyolefin resin, modified halogenated polyolefin resin etc. can be illustrated as said polyolefin resin, You may use any in the pre-processing liquid of this embodiment. Among them, there is no dehydrohalogenation reaction, and while suppressing the interaction with the coagulant (B), by forming a stable association with the thickener (C), unevenness during coating, image From the viewpoint of obtaining a pretreatment liquid excellent in quality and storage stability, it is preferable to select a non-modified polyolefin resin and / or a modified polyolefin resin, and from the viewpoint that a printed matter with excellent adhesion is obtained, a modified polyolefin It is particularly preferred to select a resin. In addition, as said modification | denaturation, acid modification, acrylic modification, urethane modification, epoxy modification etc. can be illustrated, and all can be used suitably.

The pretreatment liquid of the present embodiment may contain only one type of resin particles (A) exemplified above, or two or more types may be used in combination. In one embodiment, the pretreatment liquid is polyurethane It is preferable to include two or more types of resin particles selected from the group consisting of a resin, a polyurethane polyurea resin, a (meth) acrylic resin, an acrylic modified polyurethane resin, and a polyolefin resin. By combining and using resin particles different in characteristics and type, it is possible to form a particularly stable association with the thickener (C), and it is possible not only to be suitably compatible with unevenness in coating, image quality and adhesion. It is because it becomes the said pre-processing liquid excellent also in blocking resistance and drying property. Above all,
From the viewpoint of coexistence of the above-mentioned properties, it is particularly preferable to contain two or more types of polyolefin resin particles as the resin particles (A).

As the resin 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, Adekabon titer HUX series (made by ADEKA); Uuliano series (made by Arakawa Chemical Industries, Ltd.);
Ohara Palladium Chemical Co., Ltd .; U-Coat Series, Permarine Series (above, Sanyo Chemical Industries, Ltd.); Super Flex Series, Super Flex E series (above, Dai-ichi Kogyo Seiyaku Co., Ltd.); WBR series (Tasei Fine Chemicals Co., Ltd.) ; Hydran series (
DIC Corporation; High Tech Series (Toho Chemical Industry Co., Ltd.); Super Cron Series, Auroran Series (Nippon Paper Industries Co., Ltd.); Nichigo Poliester Series (Nippon Synthetic Chemical Industry Co., Ltd.); AQUACER Series, Hordamer Series (all, Big Chemie) Company-made)
Bamboo rack series (made by Mitsui Chemicals, Inc.); Pascall series (made by Meisei Chemical Co., Ltd.); Arrow base series (made by Unitika) etc. can be used suitably.

The amount of the resin particles (A) contained in the pretreatment liquid of the present embodiment is preferably 1 to 30% by mass, and 1 to 25% by mass in terms of solid content with respect to the total amount of the pretreatment liquid. Is more preferable, and 3 to 20% by mass is particularly preferable. By setting the compounding amount of the resin particles (A) within the above range, the association state with the thickener (C) is suitably formed, and the adhesion to the non-permeable substrate and the suppression of the coating unevenness, the image It is possible to obtain printed matter with excellent quality. Furthermore, it is preferable also from the point which the printed matter which was excellent also in dryness and blocking resistance is obtained.

The melting point of the resin particles (A) is preferably 0 to 130 ° C. More preferably 15 to
It is 105 ° C, and particularly preferably 30 to 90 ° C. When the melting point is 0 ° C. or more, the dispersion stability of the resin particles during drying is improved and the coating suitability is excellent, and when the melting point is 130 ° C. or less, the adhesion to the non-permeable 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 dried sample
Is weighed on an aluminum sample container, and then the aluminum sample container is set in a holder in a DSC measurement apparatus (for example, "DSC-60 Plus" manufactured by Shimadzu Corporation). Then, measurement is performed under a temperature rising condition of 10 ° C./min, and the temperature of the endothermic peak read from the obtained DSC chart is taken as the melting point in the present specification. In addition, indium is used for temperature calibration.

In addition, for resin particles (A) having a melting point of greater than 130 ° C., the glass transition temperature (Tg of the resin particles (A) can be obtained from the viewpoint of obtaining a printed matter excellent in adhesion to a non-permeable substrate.
It is preferable that it is -50-130 degreeC, and it is more preferable that it is 0-130 degreeC.
Furthermore, from the viewpoint of improving dispersion stability at the time of drying of the pretreatment liquid and suppressing coating unevenness,
Particular preference is given to 130 ° C. As with 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 at the inflection point of the baseline is determined, and the temperature of the intersection point is taken as the glass transition temperature.

The resin particles (A) in the present embodiment can be suitably used in any of anionic, cationic, amphoteric and nonionic types, but it is said that the resin particles (A) exhibit excellent adhesion on a non-permeable substrate. From the viewpoint, it is preferable to use nonionic or anionic resin particles,
It is particularly preferable to use anionic resin particles. In the present specification, "anionic" refers to a substance negatively charged in water, specifically, a substance having an acid value of 1 mg KOH / g or more.

The acid value of the resin particle (A) is preferably 0 to 40 mg KOH / g. From the viewpoint of securing long-term storage stability, anionic resin particles, among which the acid value is 1 to 35 m
It is more preferable to select gKOH / g, and it is particularly preferable to select an anionic resin particle having 1 to 30 mg KOH / g. The acid value of the resin particle is 1 g of the resin particle.
The number of mg of potassium hydroxide (KOH) required to neutralize the acid contained in
It can measure by potentiometric titration method using a well-known apparatus. Specifically, it is a value that can be titrated with a KOH solution in an ethanol / toluene mixed solvent, for example, using “a potentiometric automatic titration device AT-610” manufactured by Kyoto Electronics Industry Co., Ltd.

<Flocculant (B)>
The pretreatment liquid of the present embodiment contains a coagulant (B) having a specific moisture absorption rate. In the present specification, the “flocculant” destroys and aggregates the dispersed state of the pigment or resin particles contained in the aqueous inkjet ink, and / or insolubilizes the water-soluble resin and thickens the aqueous inkjet ink. It means ingredients that can be

The coagulant (B) used in the pretreatment liquid of the present embodiment contains a polyvalent metal salt and / or a cationic polymer compound from the viewpoint of being able to remarkably improve the image quality. A polyvalent metal salt or a cationic polymer compound has a strong function as an aggregating agent, and is effective for aggregation and precipitation of pigments even in a small amount, so that color mixing blur and color unevenness are eliminated and image quality is significantly improved. It is possible. Moreover, since these materials function as an aggregating agent promptly and do not inhibit the functional expression of the resin particles (A), it is considered that the adhesion to the non-permeable substrate is also improved. In the pretreatment liquid of the present embodiment, either a polyvalent metal salt or a cationic polymer compound may be selected and used, or may be used in combination.

As described above, the flocculating agent (B) used in the pretreatment liquid of the present embodiment has a moisture absorption rate of 75% by mass or less at a temperature of 40 ° C. and a relative humidity of 80%. In addition, "the moisture absorption rate" in this specification is a value specifically measured by the following method.
First, the flocculant is stored for 24 hours in an environment at a temperature of 100 ° C. and a relative humidity of 75% or less. At this time, if the coagulant is available only in the form of an aqueous solution, such as a commercial product, water is volatilized and removed in advance, and then stored under an environment of 100 ° C. and 75% or less relative humidity. Temperature 100 ° C,
After storing in an environment with a relative humidity of 75% or less, the mass of the coagulant is measured (W1 (g)), and then stored for 24 hours in an environment with a temperature of 40 ° C. and a relative humidity of 80%. And the temperature 40
After storage under an environment of 80 ° C. and a relative humidity of 80%, the mass is measured again (W2 (g)), and the moisture absorption rate is calculated by the following formula (1).

Formula (1):

Moisture absorption rate of water (% by mass) = 100 × {(W2-W1) / W1}

As described above, when the moisture absorption rate of the coagulant (B) used in the pretreatment liquid of the present embodiment is 75% by mass or less, the pretreatment liquid is applied to a non-permeable substrate and dried As the water is easily volatilized, coating unevenness can be suppressed, and the adhesion and the image quality are not impaired. Furthermore, it is preferable because a printed matter capable of retaining the above-mentioned characteristics for a long time can be obtained. Moreover, it is more preferable that the said water moisture absorption rate is 40 mass% or less from a viewpoint which the said effect expresses more suitably.

<Polyvalent metal salt>
As used herein, the term "polyvalent metal salt" refers to a metal salt composed of a divalent or higher valent metal ion and a counter anion. When a polyvalent metal salt is selected as the aggregating agent (B), any material can be used as long as it exhibits the function as the aggregating agent and has suitable solubility and diffusion. The polyvalent metal salt may be used alone or in combination of two or more.

Among them, the polyvalent metal salt is preferably a divalent metal salt. The divalent metal salt is excellent in water solubility and diffusivity, and when in contact with droplets of an aqueous inkjet ink, can be rapidly mixed to cause thickening and aggregation of the droplets. In addition, compared to trivalent or higher metal salts, the above-mentioned thickening and aggregation are not rapidly caused, so that the wetting and spreading on the non-permeable substrate can be appropriately suppressed, and as a result, the image quality is improved. Printed matter excellent in adhesion and drying properties can be obtained.

In the pretreatment liquid of the present embodiment, the divalent metal ion constituting the divalent metal salt is selected from the group consisting of calcium ion, magnesium ion, zinc ion, and iron ion from the viewpoint of high function as a coagulant. It is preferable that it is 1 type. In particular, calcium ions have the advantage of having a large ionizing tendency and tending to ionize, and thus have the advantage of having a large effect as a flocculant, and also have a small ionic radius and easily move in the pretreatment liquid and in ink droplets. It is preferably selected from the viewpoint of obtaining good image quality. Moreover, although the details are unknown, the pretreatment solution combining the calcium ion-containing coagulant (B) with the resin particles (A) and the thickener (C) is also excellent in adhesion, drying property, and blocking resistance. And from this point,
The calcium ion is suitably selected.

In addition, as counter anions of the above polyvalent metal ions, ions of inorganic acids such as chloride ion, bromide ion, nitrate ion, nitrite ion, sulfate ion, carbonate ion, etc., pantothenate ion, formate ion, acetate ion, propionone. Ions of organic acids such as acid ion, ascorbic acid ion, glycolate ion, lactate ion are preferably selected.
Furthermore, from the viewpoint of obtaining a pretreatment liquid in which the compatibility with the resin particles (A) and the thickener (C) is high and the image quality and storage stability are compatible, ions of organic acids are selected from the above. Is preferred. Among them, at least one selected from formate ion, acetate ion, propionate ion, glycolate ion and lactate ion is selected from the viewpoint of solubility in water and interaction with components in the aqueous inkjet ink. It is more preferable to select acetate ion and / or lactate ion.

The content of the polyvalent metal salt in the pretreatment liquid of the present embodiment is preferably 0.5 to 8% by mass as polyvalent metal ions with respect to the total amount of the pretreatment liquid, 1.0 to 6.5 It is more preferable that it is mass%, and it is especially preferable that it is 1.0-5.0 mass%. By setting the content of the polyvalent metal ion within the above range, long-term storage stability can be secured. In addition, it is possible to ensure the wettability of the pretreatment liquid to the base material while suppressing the color mixing blur and the color unevenness, and the printed matter is excellent in the image quality. In addition, content of the polyvalent metal ion with respect to the whole pre-processing liquid is calculated | required by following formula (2).

Formula (2):

(Content of polyvalent metal ion) (mass%) = WC × MM ÷ MC

In the formula (2), WC represents the content (% by mass) of the polyvalent metal salt relative to the total amount of the pretreatment liquid,
MM represents the molecular weight of the polyvalent metal ion constituting the polyvalent metal salt, and MC represents the molecular weight of the polyvalent metal salt.

<Cationic polymer compound>
When a cationic polymer compound is selected as the aggregating agent (B), as in the case of the polyvalent metal salt, it may exhibit the function as the aggregating agent and have suitable solubility and diffusibility. For example, any material can be used. Also, one type may be used alone, or two or more types may be used in combination. In the present specification, the "cationic polymer compound" is a compound having a cation group in the molecule and one or more types of monomers linked by a covalent bond.

Although an amino group, an ammonium group, an amide group, -NHCONH ₂ group etc. are mentioned as an example of the cationic group contained in a cationic polymer compound, It is not limited to these. Moreover, as a material used to introduce the above cationic group into the cationic polymer compound, for example, amine compounds such as vinylamine, allylamine, methyldiallylamine, ethyleneimine and the like; amide compounds such as acrylamide, vinylformamide, vinylacetamide and the like; dicyandiamide Epihalohydrin compounds such as epifluorohydrin, epichlorohydrin, methylepichlorohydrin, epibromohydrin, epiiodohydrin etc. cyclic vinyl compounds such as vinylpyrrolidone, vinylcaprolactam and vinylimidazole; amidine Compound; pyridinium salt compound; imidazolium salt compound etc. can be mentioned.

In the pretreatment liquid of this embodiment, a cationic polymer compound having a moisture absorption rate of 75% by mass or less is used as the coagulant (B), and a hydrophobically modified water-soluble urethane resin is used as the thickener (C). When used, it is preferable to use a compound comprising one or more structural units selected from the group consisting of diallylamine structural units, diallyl ammonium structural units, and epihalohydrin structural units, and at least diallyl ammonium structural units. More preferably, it contains a unit. The above-mentioned resins are all strong electrolytes, and they have good dissolution stability in the pretreatment solution and also have high function as a coagulant. Furthermore, although the details are unknown, it is difficult for the thickener (C) to suppress the aggregation action.

Among them, a resin containing a diallyl ammonium structural unit exhibits particularly excellent cohesiveness, and it is possible to obtain a printed matter with less color mixing blur and color unevenness and excellent colorability on a non-permeable substrate. preferable. From the viewpoint of availability and the like, the diallyl ammonium structural unit may be diallyl dimethyl ammonium and / or diallyl methyl ethyl ammonium,
The hydrochloride or sulfate ethyl salt is preferably selected.

On the other hand, although the reason is not clear, the printed matter using the resin containing the epihalohydrin structural unit is excellent in water resistance, and is also preferably selected from this point. In addition, as a resin containing an epihalohydrin structural unit, an epihalohydrin modified polyamine resin, an epihalohydrin modified polyamide resin, an epihalohydrin modified polyamide polyamine resin, an epihalohydrin-amine copolymer, etc. can be mentioned. From the viewpoint of availability and the like, epichlorohydrin or methyl epichlorohydrin is preferably selected as epihalohydrin.

As the above-mentioned cationic polymer compound, one synthesized by a known synthesis method may be used, or a commercially available product may be used. In addition, as a specific example of the commercial item containing a diallylamine structural unit, PAS-21CL, PAS-21, PAS-M-1L, PAS-M-1, PAS-M-
1A (manufactured by Nittobo Medical); Unisense KCA 100L, KCA 101L (manufactured by Senka). Moreover, as a commercial item of resin containing a diallyl ammonium structural unit, PAS-H-1L, PAS-H-5L, PAS-24, PAS-J-81L,
PAS-J-81, PAS-J-41 (manufactured by Nittobo Medical); Unisense FP
A1000L, FPA1001L, FPA1002L, FCA1000L, FCA100
1 L, FCA 5000 L (manufactured by Senka Co., Ltd.) can be mentioned. Furthermore, as a commercial product of a resin containing both a diallylamine structural unit and a diallyl ammonium structural unit, PAS-8
80 (manufactured by Nittobo Medical) can be mentioned. On the other hand, specific examples of commercially available products containing an epihalohydrin structural unit include: CASIOMASTER PD-1, 7, 30, A, PDT
-2, PE-10, PE-30, DT-EH, EPA-SK01, TMHMDA-E (manufactured by Yokkaichi Gosei Co., Ltd.).

The weight average molecular weight of the cationic polymer compound that can be suitably used in the pretreatment liquid of the present embodiment is 5,000 to 50,000, and more preferably 10,000 to 30,000.
It is. The weight average molecular weight of the cationic polymer compound can be measured by a conventional method. Specifically, using a GPC measurement apparatus (HLC-8120GPC manufactured by Tosoh Corp.) equipped with a TSK gel column (manufactured by Tosoh Corp.) and an RI detector, the polystyrene conversion value measured using THF as a developing solvent is Let it be the weight average molecular weight in the specification.

The content of the cationic polymer compound in the pretreatment liquid of the present embodiment is preferably 1 to 20% by mass, and 3 to 10% by mass in terms of solid content, with respect to the total amount of the pretreatment liquid. More preferable. By making the compounding quantity of a cationic high molecular compound into the said range, the viscosity of a pre-processing liquid can be included in a suitable range, and the pre-processing liquid excellent in storage stability can be obtained.

<Thickener (C)>
The pretreatment liquid of the present embodiment contains a hydrophobically modified water-soluble urethane resin as a thickener (C). In the present invention, “hydrophobic modified urethane resin” refers to a urethane resin having an alkylene group having 6 or more carbon atoms in its molecule. In addition, “water-soluble resin” means that the particle diameter is less than 5 nm when it is measured by the same method as the particle diameter of the resin particles (A) described above,
Something that can not be measured (for example, when the sample preparation does not reach a measurable concentration level)
Point to

Among them, from the viewpoint of securing long-term storage stability and rapidly increasing viscosity on a non-permeable substrate at the time of coating or drying, as a hydrophobically modified water-soluble urethane resin, the following general formula (3) or It is preferable to use the urethane resin which shows the structure of General formula (4). The urethane resin having the structure of the following general formula (3) or (4) is considered that the coagulant (B) is present around the highly hydrophilic ethylene oxide group, and the coagulant (B) is contained in the aggregate structure. It is thought that the incorporation contributes to further stabilization.

General formula (3):

R ₁ -A ₁ -R ₂ -A ₂ -[(EO) _l -A ₃ -R ₃ -A ₄ ] _m -R ₄

In general formula (3), R ₁ and R ₄ each independently represent a monovalent hydrocarbon group which may have an aromatic ring having 2 to 25 carbon atoms, and R ₂ and R ₃ are each independently And a divalent hydrocarbon group which may have an aromatic ring having 2 to 25 carbon atoms.
A _{1 to} A ₄ each independently represent a urethane bond or an ester bond, EO represents an ethylene oxide group, and l and m each represent an integer of 1 or more.

General formula (4):

_{R 5 - (EO) n -A} 5 -R 6 -A 6 - [(EO) O -A 7 -R 7 -A 8] p - (EO) q -R 8

In general formula (4), R ₅ and R ₈ each independently represent a monovalent hydrocarbon group which may have an aromatic ring having 2 to 25 carbon atoms, and R ₆ and R ₇ are each independently And a divalent hydrocarbon group which may have an aromatic ring having 2 to 25 carbon atoms.
A _{5 to} A ₈ each independently represent a urethane bond or an ester bond, EO represents ethylene oxide, and n, o, p and q each represent an integer of 1 or more.

The hydrocarbon group represented by R _{1 to} R ₈ in the general formulas (3) to (4) has a hydrocarbon chain such as an alkyl group or an alkylene group having a length of a certain length or more, which is highly hydrophobic. Do. Therefore, it is possible to interact with the resin particles (A) to form an association state. Even in the presence of the coagulant (B), long-term storage stability is ensured, and a coated article with little coating unevenness on a non-permeable substrate is obtained, thereby obtaining a print having excellent image quality. From the viewpoint of obtaining, the above general formula (3)
Preferably, two or more of R _{1 to} R _{4 in} the above and two or more of R _{5 to} R _{8 in} the general formula (4) have 6 to 25 carbon atoms, and the carbon numbers are It is more preferably 8 or more and 25 or less, and particularly preferably 10 or more and 25 or less.
In addition, in the case of the general formula (3), at least R ₁ and R ₄ each represent an alkyl group having 6 to 25 carbon atoms from the viewpoint that the association state formed between the resin particles (A) is suitable. In the case of the general formula (4), it is preferable that at least R ₅ and R ₈ be an alkyl group having 6 to 25 carbon atoms. In addition, a C6-C25 alkyl group is one form of a C6-C25 alkylene group.

As the hydrophobic modified water-soluble urethane resin, one synthesized by a known synthesis method may be used, or a commercially available product may be used. Specific examples of commercially available products include, but are not limited to, Adekanol UH series (made by Adeka), SN Thickener series (made by Sannopco), Nopearl series (made by Sannopco) and the like.

The hydrophobic modified water-soluble urethane resin used as the thickener (C) has a weight average molecular weight of 5
It is preferable that they are 1,000-100,000. In addition, long-term storage stability is ensured, and after application of the pretreatment liquid, viscosity is rapidly increased on the non-permeable substrate, and a uniform coating film without coating unevenness is obtained, resulting in excellent image quality The weight average molecular weight is preferably 10,000 to 90,000, particularly preferably 10,000 to 80,000, from the viewpoint of providing a printed matter having
It is 000. In addition, the weight average molecular weight of a thickener (C) can be measured like the case of the said cationic polymer compound.

It is preferable that the compounding quantity of a thickener (C) is 0.5-200 mass% with respect to the compounding quantity of resin particle (A) in the pre-processing liquid of this embodiment. In addition, thickening is ensured from the viewpoint of ensuring storage stability over a long period of time even in the presence of the coagulant (B) and obtaining a print having excellent image quality with little coating unevenness on a non-permeable substrate. It is more preferable that the compounding quantity of an agent (C) is 1-100 mass% with respect to the compounding quantity of the said resin particle (A). Particularly preferably, it is 5 to 100% by mass.

<Surfactant (D)>
The pretreatment liquid of the present embodiment uses a surfactant (D) in order to suppress coating unevenness and uniformly apply on a non-permeable substrate such as a film. In addition, the HLB value is preferably 13.5 or less (may be 0) from the viewpoint that uniform coating can be uniformly performed on a non-permeable substrate and a printed product having excellent image quality can be obtained. Furthermore, from the viewpoint of suppressing bubbles and repelling, HLB
The value is preferably 10.5 or less, more preferably 1.0 or more, particularly preferably 1.2 to 8.5, and most preferably 1.5 to 8.5.

The HLB (Hydrophile-Lipophile Balance) value is one of the parameters representing the hydrophilicity / hydrophobicity of the material, and the smaller the value, the higher the hydrophobicity of the material,
The larger the value, the higher the hydrophilicity of the material. There are various methods for calculating the HLB value, such as Griffin method, Davis method, and Kawakami method, and various measurement methods are also known, but in the present specification, acetylene diol surfactants and polyoxyalkyl ether are used. When the structure of the compound is clearly known like the surfactant of the system, the HLB value is calculated using the Griffin method. The Griffin method is a method of obtaining an HLB value as shown in the following formula (5) using the molecular structure and molecular weight of a target material.

Formula (5):

HLB value = 20 × (sum of molecular weight of hydrophilic portion) ÷ (molecular weight of material)

On the other hand, when a compound of unknown structure is contained as in the case of the siloxane-based surfactant described later,
For example, “surfactant handbook” (Nishiichiro et al. Ed., Industrial Books Co., Ltd., 1960), p. 324
The HLB value of the surfactant can be determined experimentally by the following method described in. Specifically, 0.5 g of a surfactant is dissolved in 5 mL of ethanol, and while stirring the solution under 25 ° C., the solution is titrated with a 2% by mass aqueous phenol solution, and the point at which the solution becomes turbid is taken as an end point. . When the amount of the phenol aqueous solution required until the end point is A (mL), the HLB value can be calculated by the following formula (6).

Formula (6):

HLB value = 0.89 × A + 1.11

The surfactant (D) used in the pretreatment liquid of the present embodiment is a siloxane-based, acetylene diol-based, acrylic, or poly-based from the viewpoint of obtaining a pretreatment liquid that can be uniformly coated on a non-permeable substrate. An oxyalkyl ether surfactant can be suitably used. In particular,
The surfactant (D) interacts with the association state formed between the resin particles (A) and the thickener (C).
Acetylene diol surfactant and / or from the viewpoint that the compatibility of
Alternatively, it is preferable to use a siloxane surfactant, and it is more preferable to use at least an acetylenic diol surfactant.

The above acetylene diol surfactants include, for example, 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 2,5,8,11-tetramethyl-6-dodecin-5, 8-diol, hexadec-8-yne-7,10-diol, 6,9-dimethyl-
Tetradec-7-yne-6,9-diol 7,10-dimethylhexadeca-8-yne-
7,10-diol and its ethylene oxide and / or propylene oxide adducts.

Moreover, when the commercial item of said acetylene diol surfactant is illustrated, Surfynol 61
, 104E, 104H, 104A, 104BC, 104DPM, 104PA, 104PG
−50, 420, 440, 465, 485, SE, SE-F, Dynol 604, 607
(Manufactured by Air Products), Olfin E1004, E1010, E1020, PD-0
01, PD-002W, PD-004, PD-005, EXP. 4001, EXP. 42
00, EXP. 4123, EXP. 4300 (manufactured by Nisshin Chemical Industry Co., Ltd.) and the like.
The above surfactants may be used alone or in combination of two or more.

The content of the surfactant (D) in the pretreatment liquid of the present embodiment is 0 with respect to the total amount of the pretreatment liquid.
. It is preferable that it is 01-10 mass%. More preferably, it is 0.1-8 mass%, More preferably, it is 0.5-6 mass%.

<Water>
It is preferable that it is 30-95 mass% with respect to the pretreatment liquid whole quantity, and, as for content of the water contained in the pretreatment liquid of this embodiment, it is more preferable that it is 40-90 mass%, and 50-85 mass. More preferably, it is%. Water enhances the mutual solubility of materials essential for the pretreatment liquid of the present embodiment, such as resin particles (A), coagulants (B), thickeners (C), surfactants (D), etc. It is an essential material to improve the storage stability of the pretreatment solution.

<Organic solvent>
The pretreatment liquid of the present embodiment may further contain an organic solvent. By using an organic solvent in combination, the solubility of the coagulant (B), the thickener (C) and the surfactant (D), and the wettability and drying properties of the pretreatment liquid can be adjusted to be suitable. In the pretreatment liquid of the present embodiment, only one organic solvent may be used, or two or more organic solvents may be used in combination.

Although there is no restriction | limiting in particular in the organic solvent which can be used for the pre-processing liquid of this embodiment, It is preferable that a water-soluble organic solvent is included. In the present specification, “water-soluble (of) organic solvent” refers to a liquid which is liquid at 25 ° C. and has a solubility in water of 25 ° C. of 1% by mass or more.

The water-soluble organic solvent used in the pretreatment liquid of the present embodiment has a static surface tension of 20 to 40 mN / m at 25 ° C. from the viewpoint of obtaining excellent wettability and drying property on a non-permeable substrate. It is preferable that it is something. Particularly preferably, it is 20 to 36 mN / m.

The static surface tension as used herein refers to the surface tension measured by the Wilhelmy method (plate method, vertical plate method) under an environment of 25 ° C.

When the pretreatment liquid of the present embodiment contains an organic solvent, the affinity with the coagulant (B), the thickener (C), and the surfactant (D) is high, and the storage stability of the pretreatment liquid is improved. It is more preferable to use a water-soluble organic solvent having one or more hydroxyl groups in the molecular structure, and using monohydric alcohols and / or dihydric alcohols (glycols) exemplified below. Is particularly preferred.

In one embodiment, the pretreatment liquid containing a water-soluble organic solvent having a boiling point of 75 to 210 ° C. under 1 atmosphere as the water-soluble organic solvent containing one or more hydroxyl groups in the molecular structure is impermeable It is particularly preferable because uniform application to a substrate can be realized, and adhesion and image quality are particularly improved. Furthermore, from the viewpoint of more preferably exhibiting the above effects, the boiling point of the water-soluble organic solvent having one or more hydroxyl groups in the molecular structure under one atmosphere is 75 to 20.
The temperature is more preferably 0 ° C., further preferably 75 to 190 ° C., and 80 to 18
Very preferably 0 ° C. In the present specification, the boiling point at 1 atm is a value measured by a known method, such as a differential thermal analysis (DTA) method or a DSC method.

The water-soluble organic solvent having one or more hydroxyl groups in the molecular structure, which is suitably used for the pretreatment liquid of the present embodiment, is exemplified as follows:
Methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2
-Monohydric alcohols such as butanol;
1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1
, 2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,5-pentanediol, 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,
Diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol # 200, polyethylene glycol # 400, dipropylene glycol,
Dihydric alcohols (glycols) such as tripropylene glycol, dibutylene glycol, etc .;
Ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl 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, tetra Ethylene glycol monobutyl ether, dipropylene glycol monopropyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, 1,2-butylene glycol monomethyl ether, glycols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol Monoalkyl ethers;
Glycerin, trimethylolpropane, 1,2,4-butanetriol, 1,2,6-
Linear polyol compounds such as hexanetriol, diglycerin, polyglycerin, etc.
Can be mentioned.
As described above, among the water-soluble organic solvents exemplified above, those having a static surface tension of 20 mN / m to 40 mN / m at 25 ° C. are suitably selected. In addition, one having a boiling point of 75 to 210 ° C. under one atmosphere is suitably selected, one having a boiling point of 75 to 200 ° C. is more suitably selected, and one having a temperature of 75 to 190 ° C. is more suitably selected. ~ 180
Those which are ° C. are very suitably selected.

Further, in the pretreatment liquid of the present embodiment, other than those exemplified above,
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 butyl methyl ether, triethylene glycol diethyl ether, tetraethylene glycol dimethyl ether, tetra ethylene glycol Glycol dialkyl ethers such as methyl ethyl ether, tetraethylene glycol butyl methyl ether, tetra ethylene glycol diethyl ether;
2-pyrrolidone, N-methylpyrrolidone, 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, N, N-dimethyl-β-2-ethylhexoxypropionamide, N, N-dimethyl-β-octoxypropionamide, N, N
-Diethyl-β-butoxypropionamide, N, N-diethyl-β-pentoxypropionamide, N, N-diethyl-β-hexoxypropionamide, N, N-diethyl-
Nitrogen-containing solvents such as β-heptoxypropionamide and N, N-diethyl-β-octoxypropionamide;
Heterocyclic compounds such as γ-butyrolactone, γ-valerolactone, δ-valerolactone, ε-caprolactone and the like;
Etc can be used.

The total amount of the compounding amount of the organic solvent contained in the pretreatment liquid of the present embodiment is 0 with respect to the total amount of the pretreatment liquid.
. It is preferably 5 to 50% by mass, more preferably 1 to 40% by mass, 3
It is especially preferable that it is -30 mass%. By setting the blending amount of the organic solvent within the above range,
While being able to obtain a pretreatment liquid in which the solubility of the coagulant (B), the thickener (C) and the surfactant (D) is compatible with the wettability to the non-permeable substrate, Regardless of the coating method, stable coating can be performed on the non-permeable substrate for a long period of time without causing printing defects.

When a water-soluble organic solvent containing one or more hydroxyl groups is used as the organic solvent, the blending amount is preferably 35 to 100% by mass with respect to the total amount of the organic solvent,
The content is more preferably 50 to 100% by mass, and particularly preferably 65 to 100% by mass. It is because the effect by the water-soluble organic solvent containing 1 or more of hydroxyl groups is suitably expressed by containing a compounding quantity in the said range.

Moreover, in the pretreatment liquid of the present embodiment, the content of the organic solvent having a boiling point of 240 ° C. or higher at 1 atmospheric pressure is preferably less than 10% by mass with respect to the total amount of the pretreatment liquid (0 mass% But) By not containing the organic solvent having a boiling point of 240 ° C. or more, or by containing the organic solvent in the above range, a printed matter excellent in image quality can be obtained and the drying property of the pretreatment liquid is sufficient. It becomes.

Furthermore, for the same reason as described above, in addition to the content of the organic solvent having a boiling point of 240 ° C. or higher at 1 atm being less than 10% by mass with respect to the total amount of the pretreatment liquid, The content of the organic solvent having a boiling point of 220 ° C. or higher is preferably less than 15% by mass, more preferably less than 10% by mass, and less than 5% by mass with respect to the total amount of the pretreatment liquid. Is particularly preferred.

<PH adjuster>
The pretreatment liquid of the present embodiment can contain a pH adjuster. By using a pH adjuster, while suppressing damage to the member used for a coating apparatus, pH fluctuation over time is suppressed, the performance of a pretreatment liquid is maintained for a long time, and preservation stability is maintained.・ It can be improved. p
There is no restriction | limiting in the material which can be used as H regulator, Moreover, only 1 type may be used and 2 or more types may be used together.

Specifically, when the pretreatment liquid is to be basified, alkanolamines such as dimethylethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, etc .; ammonia water; lithium hydroxide, sodium hydroxide, potassium hydroxide For example, hydroxides of alkali metals such as, for example, carbonates of alkali metals such as lithium carbonate, sodium carbonate, sodium hydrogencarbonate and potassium carbonate can be used. In the case of 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 and the like can be used.
The above pH adjusters may be used alone or in combination of two or more.

The content of the pH adjuster is preferably 0.01 to 5% by mass, and more preferably 0.05 to 4.5% by mass, based on the total amount of the pretreatment liquid. By keeping the compounding amount of the pH adjuster within the above range, pH change due to the external stimulus such as dissolution of carbon dioxide in the air, resin particles (A), flocculant (B), thickener (C), interface It does not inhibit the onset of the effect of the active agent (D).

<Colorant>
In a preferred embodiment of the present invention, the pretreatment liquid of the present embodiment is substantially free of a colorant such as a pigment or a dye. By using a substantially transparent pre-treatment liquid which does not contain a coloring agent, it is possible to obtain a printed matter which makes use of the tint and transparency unique to a substrate. In the present specification, "does not substantially contain" means that the intentional addition of the material is not recognized to the extent that the effect of the present invention is prevented, and, for example, impurities and subcomponents It does not exclude unintended contamination as a product. Specifically, the material is not contained by 2.0% by mass or more, preferably 1.0% by mass or more, and more preferably 0.5% by mass or more based on the total amount of the pretreatment liquid. It is not included, and particularly preferably not included 0.1% by mass or more.

On the other hand, in another preferred embodiment, the pretreatment liquid of the present embodiment contains a white pigment as a colorant. By using a white pretreatment liquid on a colored and / or transparent substrate, a print having excellent sharpness and visibility can be obtained. When the pretreatment liquid of the present embodiment contains a white pigment, conventionally known materials can be optionally 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; resin particles such as hollow resin particles and non-hollow resin particles;
Etc. can be used.

<Other materials>
In addition, in the pretreatment liquid of the present embodiment, additives such as preservatives can be appropriately used as needed to obtain desired physical property values. When these additives are used, the blending amount thereof is preferably 0.01 to 5% by mass, and more preferably 0.01 to 3% by mass, with respect to the total amount of the pretreatment liquid. Excessive blending may inhibit the functions of resin particles (A), flocculant (B), thickener (C) and surfactant (D) in the pretreatment liquid. Therefore, the addition amount is preferably in the above range.

  Moreover, it is preferable that the pre-processing liquid of this embodiment does not contain a polymerizable monomer substantially.

<Physical properties of pretreatment liquid>
The pretreatment liquid of the present embodiment preferably has a viscosity of 5 to 200 mPa · s at 25 ° C., more preferably 5 to 180 mPa · s, and still more preferably 8 to 160 mPa · s. It is particularly preferable that the viscosity is -150 mPa · s. The pretreatment liquid satisfying the above viscosity range can be coated on the non-permeable substrate without unevenness, so that the printed matter is excellent in image quality and adhesion. The viscosity of the pretreatment liquid is, for example, according to the viscosity of the treatment liquid, for example, using an E-type viscometer (TVE 25 L-type viscometer manufactured by Toki Sangyo Co., Ltd.) or a B-type viscometer (TVB 10 viscometer manufactured by Toki Sangyo Co., Ltd.) Can be measured.

In addition, the static surface tension of the pretreatment liquid of the present embodiment imparts suitable wettability on the non-permeable substrate, and by forming a uniform, uniform pretreatment liquid layer, the image quality is excellent. From the viewpoint of obtaining the printed matter, it is preferably 20 to 40 mN / m, more preferably 21 to 37 mN / m, and particularly preferably 22 to 35 mN / m. The static surface tension in the present specification is a value based on the Wilhelmy method (plate method, vertical plate method) under an environment of 25 ° C. For example, an automatic surface tension meter CBVP-Z (manufactured by Kyowa Interface Science Co., Ltd.)
And a platinum plate.

<Method of producing pretreatment liquid>
The pretreatment liquid of the present embodiment comprising the above-mentioned components includes, for example, resin particles (A) and coagulants (B).
, A thickener (C), a surfactant (D) and, if necessary, an organic solvent, a pH adjuster, and appropriately selected additive components as mentioned above were added and stirred and mixed. After that, it is manufactured by filtering as needed. However, the method for producing the pretreatment liquid is not limited to the above. For example, when a white pigment is used as a colorant, a white pigment dispersion containing the white pigment and water is prepared in advance, and then resin particles (A), flocculant (B), thickener (C), interface You may mix with an activator (D).

In addition, in the case of stirring and mixing, you may heat the said mixture in 40-100 degreeC as needed. However, it is preferable to heat at the temperature below the minimum film-forming temperature (MFT) of resin particle (A).

<Ink set>
The pretreatment liquid of the present embodiment can be used in the form of an ink set in combination with one or more aqueous inkjet inks. Below, the component of the water-based inkjet ink (Hereinafter, it is also only mentioned "the water-based inkjet ink (water-based ink, ink) of this embodiment") which comprises the ink set of this embodiment is demonstrated.

<Pigment>
The aqueous inkjet ink of the present embodiment contains a pigment as a coloring material from the viewpoint of having blocking resistance, water resistance, light resistance, weather resistance, gas resistance and the like. Any of known organic pigments and inorganic pigments can be used as the pigment.
These pigments are preferably contained in the range of 2 to 20% by mass, more preferably 2.5 to 15% by mass, and more preferably 3 to 10% by mass with respect to the total amount of the aqueous ink. It is particularly preferred to be included.
In the case of white ink, the pigment content is 3 to 4 with respect to the total amount of the white ink.
The content is preferably 0% by mass, more preferably 5 to 35% by mass, and particularly preferably 7 to 30% by mass.
By setting the pigment content to 2% by mass or more (3% by mass or more in the case of white ink),
A print having sufficient color developability and sharpness can be obtained. Moreover, the content of the pigment is 20% by mass or less (
By setting the viscosity to 40% by mass or less in the case of white ink, the viscosity of the water-based ink can be contained in a range suitable for ink jet printing, and the storage stability of the water-based ink becomes good. Stability can be ensured.

Examples of cyan organic pigments that can be used in the aqueous ink of this embodiment include C.I.
I. Pigment blue 1, 2, 3, 15: 3, 15: 4, 15: 6, 16, 22, 60,
64, 66 and the like. Among them, C.I. from the point of being excellent in color developability and light resistance. I. One or more selected from the group consisting of pigment blue 15: 3 and 15: 4 can be preferably used.

As a magenta organic pigment, for example, C.I. I. Pigment red 5, 7, 12, 2
2, 23, 31, 48 (Ca), 48 (Mn), 49, 52, 53, 57 (Ca), 57
: 1, 112, 122, 146, 147, 150, 185, 202, 209, 238, 2
42, 254, 255, 266, 269, 282, C.I. I. Pigment violet 19
, 23, 29, 30, 37, 40, 43, 50 and the like 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 C.I. Pigment Violet 19 can be preferably used.

From the viewpoint of further enhancing color development, 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 and C.I. I. Pigment red 202
And C. I. Pigment violet 19 and C.I. I. Pigment red 209 and C.I. I. Pigment violet 19 and C.I. I. Pigment red 282 and C.I. I. Pigment violet 19 and C.I. I. Pigment red 122 and C.I. I. Pigment red 150 and C.I. I. Pigment red 122 and C.I. I. Pigment red 185 and C.I. I.
Pigment red 122 and C.I. I. Pigment red 269, and the like.

Moreover, as a yellow organic pigment, for example, C.I. I. Pigment yellow 12, 13 and 1
4, 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, etc. can be used. Among them, C.I. I. Pigment yellow 12, 13, 14, 74, 120, 1
One or more selected from the group consisting of 80, 185, and 213 can be preferably used.

In addition, as the black organic pigment, for example, aniline black, lumogen black, azomethine azo black and the like can be used. A plurality of chromatic pigments such as the cyan pigment, the magenta pigment, the yellow pigment, the orange pigment, the green pigment, and the brown pigment described above may be used in combination to form a black pigment.

In the aqueous inkjet ink of the present embodiment, feature pigments such as an orange pigment, a green pigment, and a brown pigment can also be used. 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.

There is no limitation in particular in the inorganic pigment which can be used by the aqueous inkjet ink of this embodiment, For example, carbon black and iron oxide can be used as a black pigment, and titanium oxide can be used as a white pigment.

As carbon black which can be used in the water-based ink of the present embodiment, furnace black,
Channel black and acetylene black can be mentioned. Among these carbon blacks, the primary particle diameter is 11 to 50 nm, and the specific surface area by BET method is 50 to 400 m ^2.
It is preferable that the amount per gram of the volatile component is 0.5 to 10% by mass and the pH is 2 to 10. As commercially available products having such characteristics, for example, No. 25, 30, 33, 40, 44, 45, 5
2, 850, 900, 950, 960, 970, 980, 1000, 2200 B, 230
0, 2350, 2600; MA7, MA8, MA77, MA100, MA230 (or more,
Mitsubishi Chemical Corporation); RAVEN 760UP, 780UP, 860UP, 900P, 1000
P, 1060 UP, 1080 UP, 1255 (all manufactured by Birla Carbon Co., Ltd.); REGAL
330R, 400R, 660R, MOGUL L (above, made by Cabot Corporation); Nipex
160 IQ, 170 IQ, 35, 75; Printe X 30, 35, 40, 45, 55,
75, 80, 85, 90, 95, 300; Special Black 350, 550; N
E.g., erox 305, 500, 505, 600, 605 (all manufactured by Orion Engineered Carbons, Inc.) and the like can be mentioned, and any of them can be preferably used.

As titanium oxide, either anatase type or rutile type can be used.
It is preferable to use the rutile type also in order to improve the hiding property of the printed matter. The production method of titanium oxide may be either chlorine method or sulfuric acid method, but titanium oxide produced by chlorine method is preferably used because whiteness is high.

Moreover, it is preferable that the titanium oxide used by the aqueous | water-based inkjet ink of this embodiment is surface-treated by the inorganic compound and / or the organic compound. Examples of inorganic compounds include compounds of silicon (Si), aluminum, zirconium, tin, antimony, titanium, and hydrated oxides thereof. Moreover, polyhydric alcohols, alkanolamines or derivatives thereof, higher fatty acids or metal salts thereof, polysiloxane compounds, organic metal compounds can be mentioned as examples of organic compounds. Among these, polyhydric alcohols or derivatives thereof are preferably used because they can highly hydrophobize the titanium oxide surface and improve the storage stability of the ink.

In the water-based inkjet ink of the present embodiment, a plurality of the above-mentioned pigments can be mixed and used in order to keep the hue and color developability of the printed matter in a suitable range. For example, to a black ink using a carbon black pigment, a small amount of one or more pigments selected from cyan organic pigments, magenta organic pigments, orange organic pigments, and brown organic pigments in order to improve the color tone at low printing rate You may add.

<Resin for pigment dispersion>
(1) A method of adsorbing and dispersing a water-soluble pigment dispersion resin on a pigment surface as a method of stably dispersing and holding the pigment in an aqueous ink, (2) a pigment of a water-soluble and / or water-dispersible surfactant (3) A method of chemically and physically introducing a hydrophilic functional group on the pigment surface and dispersing it in the ink without a dispersing resin or surfactant (self-dispersible pigment), 4) A method of coating the pigment with a water-insoluble resin and dispersing it in the ink by using another water-soluble pigment dispersion resin or surfactant according to need can be mentioned.

In the aqueous ink used in the present embodiment, the method of (1) or (4) above, that is, the method of using a pigment dispersing resin is selected, and the pigment dispersing resin has an aromatic ring structure. 20 to 90 mass% of the monomer based on the total amount of monomers constituting the pigment dispersion resin
It is preferable to include. This is because of the improvement in adhesion and image quality due to the π-cation interaction formed by the aromatic ring contained in the pigment dispersion resin and the coagulant (B) contained in the pretreatment liquid,
The object is to ensure and improve the storage stability of an aqueous inkjet ink containing a water-soluble organic solvent. In the present specification, the term "resin for pigment dispersion" means the above (1) or (4).
This term is defined as a general term for a water-soluble pigment dispersion resin used in the method of (1) or a water-insoluble resin used in the method of (4) above. Moreover, "water-insoluble resin" refers to what is 25 degreeC * 1 mass% aqueous solution of resin which becomes object transparently in naked eye.

Among the above, it is particularly preferable to select the method using the water-soluble pigment dispersion resin of (1) in the aqueous ink of the present embodiment. This selects the monomer composition and molecular weight that make up the resin
By examining it, it is possible to easily adjust the resin adsorption ability to the pigment and the charge of the pigment dispersion resin,
As a result, it is possible to improve the storage stability of the ink and to control the pigment aggregation ability by the pretreatment liquid of the present embodiment.

The type of resin for pigment dispersion is not particularly limited. For example, (meth) acrylic resin, styrene- (meth) acrylic resin, (anhydride) maleic resin, styrene- (anhydride) maleic resin, olefin- (anhydride) Maleic acid resin, polyurethane resin, polyurea resin, polyurethane urea resin, polyester resin, etc. can be used. Among them, (meth) acrylic resin, styrene- (meth) acrylic resin, polyurethane resin, polyester resin may be used in terms of the size of material selectivity including a monomer having an aromatic ring structure and ease of synthesis. Particularly preferred. In addition, the pigment dispersion resin described above can be synthesized by a known method or a commercially available product can be used.

The resin for pigment dispersion used in the aqueous inkjet ink of the present embodiment preferably contains 20 to 90% by mass of a monomer having an aromatic ring structure, but the amount thereof is 20 to 20 parts by weight of the resin for pigment dispersion. It is preferable that it is 80 mass%, and it is especially preferable that it is 20-70 mass%. By keeping the amount of the aromatic ring structure in the above range, the effect of improving the adhesion and image quality utilizing the π-cation interaction, and securing and improving the storage stability in the aqueous ink containing the water-soluble organic solvent having a low boiling point The effect of is preferred.

In one embodiment, the pigment dispersing resin preferably contains an alkyl group having 8 to 36 carbon atoms in addition to the aromatic ring structure. By setting the carbon number of the alkyl group to 8 to 36, the pigment dispersibility is improved, and the pigment is easily fixed uniformly on the pre-treatment liquid, and the improvement of the drying property and the adhesiveness can be realized. From the viewpoint of optimizing the compatibility with the water-soluble organic solvent in the aqueous inkjet ink as the carbon number of the alkyl group and improving the drying property of the printed matter, it preferably has 10 carbon atoms.
To 30 and more preferably 12 to 24 carbon atoms. The alkyl group has 10 to 10 carbon atoms
The range of 36 may be linear or branched, but a linear one is preferable.
As a linear alkyl group, lauryl group (C12), myristyl group (C14), cetyl group (C1)
6) Stearyl group (C18), arachyl group (C20), behenyl group (C22), lignoceryl group (C24), serotoyl group (C26), montanyl group (C28), melissyl group (C30), dotriacontanyl group (C32), tetratriacontanyl group (C34), hexatriacontanyl group (C36) and the like.

The content of the alkyl chain-containing monomer having 10 to 36 carbon atoms in the resin for pigment dispersion is the reduction in viscosity of the pigment dispersion, the abrasion resistance of the printed matter, the drying resistance, the blocking resistance and the gloss It is preferable that it is 5-60 mass% from a viewpoint of making compatibility with property, it is more preferable that it is 15-55 mass%, and it is especially preferable that it is 25-50 mass%.

In one embodiment, it is also preferable that the pigment dispersing resin contains an alkylene oxide group in addition to the aromatic ring structure. By introducing an alkylene oxide group, the hydrophilic / hydrophobicity of the pigment dispersion resin can be arbitrarily adjusted, and the storage stability of the aqueous ink can be improved. When a water-soluble pigment-dispersed resin is used as a pigment-dispersing resin in order to suitably exhibit the above-mentioned function, it is preferable to select an ethylene oxide group as the alkylene oxide group. Similarly, when a water-insoluble resin is used as the pigment dispersion resin, 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 resin for pigment dispersion is from the viewpoint of achieving both the reduction in viscosity of the pigment dispersion, the storage stability of the aqueous ink, and the adhesion of the printed matter.
It is preferably 5 to 40% by mass, more preferably 10 to 35% by mass, 1
Particularly preferred is 5 to 30% by mass.

In addition, the method of said (1) is selected as a method of disperse | distributing and holding a pigment stably in aqueous ink, ie, when using water-soluble pigment dispersion resin as resin for the said pigment dispersion, the solubility to an ink is raised. Therefore, it is preferable to neutralize the acid group in the pigment dispersion resin with a base. From the viewpoint that the pigment dispersion resin can be dissolved in the ink without inhibiting the effect of the coagulant (B) in the pretreatment liquid, the pH of the 10% by mass aqueous solution of the pigment dispersion resin is 7 to 11.5 It is preferable to add a base so that it may become, and it is more preferable to add so that it may become 7.5-11.

As the above bases for neutralizing the resin for pigment dispersion, alkanolamines such as diethanolamine, triethanolamine and N-methyldiethanolamine; aqueous ammonia; alkali metals such as lithium hydroxide, sodium hydroxide and potassium hydroxide And the carbonates of alkali metals such as lithium carbonate, sodium carbonate, sodium hydrogencarbonate and potassium carbonate.

In addition, as a method of stably dispersing and holding the pigment in the ink, the method of the above (1) is selected, that is, when a water-soluble pigment dispersion resin is used as the pigment dispersion resin, the acid value is 30 to 375 mg KOH It is preferable that it is / g. By keeping the acid value within the above range, the solubility of the pigment dispersion resin in water can be secured, and the interaction between the pigment dispersion resins becomes suitable, thereby suppressing the viscosity of the pigment dispersion. The reason is that Acid number is 30
If it is mg KOH / g or more, the solubility in water is good, the viscosity of the pigment dispersion can be suppressed, and if it is 375 mg KOH / g or less, the storage stability of the aqueous inkjet ink is excellent. The acid value of the pigment dispersion resin is more preferably 65 to 340 mg KOH / g, still more preferably 100 to 300 mg KOH / g, and particularly preferably 135 to 35 mg KOH / g.
It is 270 mg KOH / g.

On the other hand, when the method of the above (4) is selected, that is, when a water-insoluble resin is used as the resin for dispersing the pigment, the acid value thereof is preferably 0 to 100 mg KOH / g, 5 to 90
It is more preferable that it is mgKOH / g, still more preferably 10-80 mgKOH / g
It is. By keeping the acid value in the above range, a printed material having excellent blocking resistance and abrasion resistance can be obtained.

The acid value of the resin for pigment dispersion is the number of mg of potassium hydroxide (KOH) required to neutralize the acid contained in 1 g of the resin for pigment dispersion, and it is in an ethanol / toluene mixed solvent. And the value titrated with a KOH solution. The said measurement can be performed, for example using Kyoto Electric Industry Co., Ltd. "potentiometric automatic titration apparatus AT-610."

The molecular weight of the pigment dispersing resin is preferably in the range of 1,000 to 300,000, and more preferably in the range of 5,000 to 200,000. When the weight average molecular weight is in the above range, the pigment is stably dispersed in water, whereby the storage stability of the water-based ink is improved, and the viscosity adjustment when used in the water-based ink can be easily performed. When the weight average molecular weight is 1,000 or more, since the pigment dispersion resin is difficult to dissolve in the water-soluble organic solvent added to the aqueous ink, the adsorption of the dispersion resin to the pigment becomes strong, The storage stability of the ink is improved. Weight average molecular weight 300,00
If it is 0 or less, not only the viscosity at the time of dispersion can be suppressed to a low level, but also the ejection stability from the ink jet head becomes good, and stable printing can be realized over a long period of time. The weight average molecular weight of the resin for pigment dispersion can be measured by the same method as the weight average molecular weight of the above-mentioned cationic polymer compound.

In the aqueous inkjet ink of the present embodiment, the compounding amount of the pigment dispersing resin is preferably 2 to 60% by mass with respect to the pigment. The blending amount of resin for pigment dispersion is 2 to the pigment.
By setting it as 60 mass%, while suppressing the viscosity of a pigment dispersion liquid and improving the storage stability of the said pigment dispersion liquid and aqueous inkjet ink, when it mixes with the pre-processing liquid of this embodiment, it aggregates rapidly. Happens. More preferably, the ratio of the pigment to the resin for dispersing the pigment is 4 to 55% by mass,
More preferably, it is 5 to 50% by mass.

As described later, the aqueous inkjet ink of the present embodiment preferably contains a binder resin. When a water-soluble pigment dispersion resin is used as a pigment dispersion resin and a water-soluble resin is used as a binder resin, JIS K 5101-1-J, for example, can be used as a method for determining the water-soluble pigment dispersion resin and the binder resin. The following method may be mentioned, to which the method described in 4 is applied mutatis mutandis.

Well mixed primary particle diameter 15 to 25 nm, carbon black 20 parts nitrogen adsorption specific surface area 120~260m ² / g, DBP absorption (granular) 40~80cm ³ / 100g, and 10 parts of resin, and 70 parts of water After pre-mixing, 0.5 m diameter beads for grinding
Dispersion is performed for 2 hours using a 0.6 L volume bead mill (for example, “DYNO MILL” manufactured by Shinmaru Enterprises, Inc.) filled with 1800 parts of zirconia beads of m. After dispersion, the viscosity of the obtained carbon black dispersion at 25 ° C. is measured using an E-type viscometer (for example, an ELD-type viscometer manufactured by Toki Sangyo Co., Ltd.), and then the carbon black dispersion is subjected to 70 ° C. Store in a thermostat for one week, and measure the viscosity again. At this time, the viscosity of the dispersion immediately after dispersion is 10
If the viscosity is 0 mPa · s or less and the absolute value of the viscosity change rate of the carbon black dispersion before and after storage is 10% or less, the resin is judged to be a water-soluble pigment-dispersed resin.

<Water-soluble organic solvent>
The aqueous inkjet ink of the present embodiment preferably contains a water-soluble organic solvent. Also,
The amount of the water-soluble organic solvent having a boiling point of 250 ° C. or higher at 1 atm is preferably 5% by mass or less (may be 0% by mass) with respect to the total amount of the aqueous inkjet ink. By setting the amount of the high-boiling water-soluble organic solvent to 5% by mass or less, the drying property and the ejection stability of the aqueous inkjet ink become good, and when combined with the pretreatment liquid, defects such as bleeding occur. In addition, an aqueous ink having good blocking resistance can be obtained. Further, from the viewpoint of further improving the image quality and the 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 (all 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 at 1 atmospheric pressure is preferably 5% by mass or less (may be 0% by mass) with respect to the total amount of the aqueous ink.
It is particularly preferable that the content be 2% by mass or less (or 0% by mass). The amount of the water-soluble organic solvent having a boiling point of 220 ° C. or more at 1 atm is calculated including the water-soluble organic solvent having a boiling point of 250 ° C. or more at 1 atm.

In one embodiment, the weighted boiling point average value under 1 atmosphere of the water-soluble organic solvent contained in the aqueous inkjet ink is preferably 145 to 215 ° C., and 150 to 200 ° C.
It is more preferable that it is ° C, and it is particularly preferable that it is 155 to 190 ° C. By setting the weighted boiling point average value of the water-soluble organic solvent within the above range, printed matter excellent in image quality can be obtained even when printing at high speed when combined with the pretreatment liquid of the present embodiment, and discharging The stability is also excellent. In addition, the water-soluble organic solvent whose boiling point is 250 degreeC or more under said 1 atmospheric pressure, and the water-soluble organic solvent whose boiling point is 220 degreeC or more shall be included in calculation of the said weighted boiling point average. In addition, the weighted boiling point average value under 1 atmospheric pressure is obtained by adding the multiplication value of the boiling point under 1 atmospheric pressure and the mass ratio to the total water soluble organic solvent calculated for each water soluble organic solvent. Value.

The total amount of the water-soluble organic solvent used in the aqueous inkjet ink of the present embodiment is preferably 3 to 40% by mass with respect to the total amount of the aqueous inkjet ink. Furthermore, from 5 to 35% by mass from the viewpoint of securing discharge stability from the nozzle and sufficient wettability and drying when combined with the pretreatment liquid, and obtaining a print excellent in adhesion and image quality. And more preferably 8 to 30% by mass. By setting the total amount of the water-soluble organic solvent to 3% by mass or more, the moisture retention of the ink becomes good, and the ink becomes excellent in the ejection stability. In addition, by setting the content of the water-soluble organic solvent to 40% by mass or less, an ink having a good drying property can be obtained, and a printed matter excellent in image quality can be obtained. In addition, resin for pigment dispersion, binder resin described later,
It is preferable to contain a glycol ether-based solvent and / or an alkyl polyol-based solvent from the viewpoint of the compatibility with the pretreatment ink and the material component contained in the aqueous inkjet ink such as surfactant, and the pretreatment liquid.

Ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl 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 Ether, dipro Glycol monobutyl ether, tripropylene glycol monomethyl ether, 1,2-butylene glycol monomethyl ether, 3-methoxybutanol, 3-methyl-3-methoxybutanol, glycol monoalkyl ethers such as;
Glycol dialkyl ethers such as diethylene glycol diethyl ether, diethylene glycol isopropyl methyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol methyl ethyl ether and the like can be mentioned.

In particular, among the above glycol ether solvents, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, among the above glycol ether solvents, in terms of being able to simultaneously achieve excellent moisture retention and drying. 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, 3-methoxy Butanol, diethylene glycol butyl methyl ether, triethylen It is preferable to select a glycol methyl ethyl ether.

Further, as an alkyl polyol solvent having a boiling point of less than 250 ° C. under one atmosphere pressure, for example, 1,2-ethanediol, 1,2-propanediol, 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-
Methyl pentane-2,4-diol, 2-ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol and the like can be mentioned.

Among them, among the above alkyl polyol solvents, 1,2-ethanediol, 1,2-propanediol, 1,2-butanediol, 1,2-diol, and the like, from the viewpoint of being able to simultaneously achieve excellent moisturizing property and drying property. It is preferable to select pentanediol and 1,2-hexanediol. More preferred are 1,2-ethanediol, 1,2-propanediol and 1,2-butanediol.

<Binder resin>
The aqueous inkjet ink of the present embodiment preferably contains a binder resin. The form of the binder resin may be either a water-soluble resin or resin particles, and may be used in combination of two or more types according to the characteristics required for the aqueous inkjet ink and the printed matter. For example, resin particles can be used to lower the viscosity of an aqueous inkjet ink and to incorporate a larger amount of resin, which is suitable for enhancing the resistance of printed matter. In addition, the aqueous inkjet ink using a water-soluble resin as a binder resin is excellent in the ejection stability and the image quality of the printed matter when combined with the pretreatment liquid of the present embodiment.

Moreover, the kind of resin which can be used suitably as binder resin is the same as that of the case of the resin particle (A) contained in a pre-processing liquid. Among them, from the viewpoint of storage stability of aqueous ink jet ink and adhesion and abrasion resistance of printed matter when combined with the pretreatment liquid of the present embodiment, (meth)
Acrylic resin, styrene- (meth) acrylic resin, polyurethane resin, polyurea resin,
Polyurethane urea resin and polyolefin resin are preferably used.

When a water-soluble resin is used as the binder resin, the weight average molecular weight is 5,000 to 80, from the viewpoint of achieving both the discharge stability of the aqueous inkjet ink and the abrasion resistance of the printed matter.
It is preferably in the range of 000, more preferably in the range of 8,000 to 60,000, and particularly preferably in the range of 10,000 to 50,000. For the same reason, the acid value of the water-soluble resin is preferably 5 to 80 mg KOH / g, and the acid value is 1
More preferably, it is 0 to 50 mg KOH / g.

The content of the binder resin in the total amount of the aqueous inkjet ink is preferably 1 to 20% by mass, more preferably 2 to 15% by mass, and particularly preferably 3% by mass of the total amount of the aqueous inkjet ink in terms of solid content. And 10% by mass.

<Surfactant>
In the water-based ink of the present embodiment, it is preferable to use 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 ink jet head will be wetted by the aqueous ink, and the ejection stability will be impaired, so selection of the type and amount of surfactant is very important. From the viewpoint of securing the wettability to the substrate and optimizing the ejection stability from the nozzle, it is preferable to use a siloxane-based, acetylene diol-based or fluorine-based surfactant. Among them, it is particularly preferable to use a siloxane type or acetylene diol type surfactant. The amount of surfactant added is the total amount of aqueous ink,
0.01-5.0 mass% is preferable, and 0.05-3.0 mass% is still more preferable.

The surfactant used in the aqueous ink of the present embodiment can be synthesized by a known method or a commercially available product. When a surfactant is selected from commercial products, for example, as a siloxane surfactant, BY16-201, FZ-77, FZ-2104, FZ-2
110, FZ-2162, F-2123, L-7001, L-7002, SF8427,
SF8428, SH3749, SH8400, 8032ADDITIVE, SH3773
M (Toray Dow Corning), Tegoglide 410, Tegoglide 43
2, Tegoglide 435, Tegoglide 440, Tegoglide 450
, Tegotwin 4000, Tegotwin 4100, Tegowet 250, Te
gowet 260, Tegowet 270, Tegowet 280 (manufactured by Evonik Degussa), SAG-002, SAG-503A (manufactured by Nisshin Chemical Industry Co., Ltd.), BYK-331, BY
K-333, BYK-345, BYK-346, BYK-347, BYK-348, BY
K-349, BYK-UV 3500, BYK-UV 3510 (manufactured by Bick Chemie), KF
-351A, KF-352A, KF-353, KF-354L, KF-355A, KF-
6004, KF-6011, KF-6012, KF-6013, KF-6015, KF-
6016, KF-6017, KF-6043, KF-615A, KF-640, KF-6
42, KF-643 (Shin-Etsu Chemical Co., Ltd.), etc.,
As fluorinated surfactants, ZonylTBS, FSP, FSA, FSN-100,
FSN, FSO-100, FSO, FS-300, Capstone FS-30, FS
-31 (DuPont), PF-151N, PF-154N (made by Omnova) can be used.
In addition, in the case of an acetylene diol surfactant, the thing similar to the commercial item which can be used for the said pre-processing liquid can be used. The above surfactants may be used alone or in combination of two or more.

The surfactant used in the aqueous ink and the surfactant used in the pretreatment liquid may be the same or different. When using each different surfactant, it is preferable to determine the compounding amount after paying attention to the surface tension of both.

<Water>
The water contained in the aqueous ink of the present embodiment is not general water containing various ions,
It is preferred to use ion exchanged water (deionized water).

The content of water that can be used in the water-based ink of the present embodiment is 20% of the total mass of the ink.
It is preferable that it is -90 mass% of range.

<Other ingredients>
In the aqueous ink of the present embodiment, in addition to the above components, a pH adjusting agent can be added as needed to obtain an ink having desired physical properties, and a material having pH adjusting ability is arbitrarily selected. can do. When basifying, alkanolamines such as dimethylethanolamine, diethanolamine, triethanolamine and N-methyldiethanolamine; ammonia water; hydroxides of alkali metals such as lithium hydroxide, sodium hydroxide and potassium hydroxide; carbonate Carbonates of alkali metals such as lithium, sodium carbonate, sodium hydrogencarbonate and potassium carbonate can be used. For acidification, use 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. be able to. The above pH adjusters may be used alone or in combination of two or more.

The content of the pH adjuster is preferably 0.01 to 5% by mass, more preferably 0.1 to 3% by mass, and more preferably 0.2 to 1.5% by mass, based on the total amount of the aqueous inkjet ink.
It is most preferable that By keeping it in the above-mentioned range, the aggregation effect by the aggregating agent (B) is inhibited when the pretreatment liquid and the aqueous inkjet ink come into contact without causing a pH change due to the dissolution of carbon dioxide in the air or the like. Without having to do this, the effects of the present invention can be suitably expressed.

Further, in addition to the above components, the aqueous inkjet ink of the present embodiment may be added with an antifoaming agent, an antiseptic agent, an infrared absorber, an ultraviolet absorber, etc. in order to obtain an ink having desired physical properties as required. Agents can be added as appropriate. The addition amount of these additives is preferably 0.01 to 5% by mass with respect to the total mass of the ink.

In addition, it is preferable that the aqueous | water-based inkjet ink of this embodiment does not contain a polymerizable monomer substantially similarly to a pre-processing liquid.

<Set of aqueous inkjet ink>
The aqueous inkjet ink of the present embodiment may be used in a single color, but can also be used as a set of aqueous inkjet ink in which a plurality of colors are combined according to the application.
The combination is not particularly limited, but full color images can be obtained by using three colors of cyan, yellow and magenta. In addition, the blackness can be improved by adding the black ink, and the visibility of characters and the like can be improved. It is also possible to improve color reproducibility by adding colors such as orange and green.
In the case of a transparent film substrate, which is an example of a non-penetrable substrate, a clear image can be obtained by printing white ink, and in particular, the sharpness and visibility of characters printed with black ink can be improved. You can raise it. Therefore, when using a transparent film substrate, at least white ink and black ink are preferably combined.

<Method of producing aqueous inkjet ink>
The aqueous inkjet ink of the present embodiment containing the components described above is produced, for example, through the following process. However, the method for producing the aqueous inkjet ink of the present embodiment is not limited to the following.

(1) Production of pigment dispersion When a water-soluble pigment-dispersed resin is used as a resin for pigment dispersion, the water-soluble pigment-dispersed resin, water, and, if necessary, a water-soluble organic solvent are mixed and stirred to obtain water solubility. A pigment dispersion resin mixed solution is prepared. A pigment is added to the water-soluble pigment-dispersed resin mixture, and mixing and stirring (premixing)
After that, dispersion processing is performed using a dispersing machine. Thereafter, centrifugation, filtration and adjustment of solid content concentration are carried out as necessary to obtain a pigment dispersion.

Moreover, when manufacturing the dispersion liquid of the pigment coat | covered with water-insoluble resin, water-insoluble resin solution which dissolved water-insoluble resin in organic solvents, such as methyl ethyl ketone, beforehand, neutralized the said water-insoluble resin as needed. Make A pigment and water are added to the water-insoluble resin solution, and after mixing and stirring (pre-mixing), dispersion treatment is performed using a dispersing machine. Thereafter, the organic solvent is distilled off by distillation under reduced pressure, and if necessary, centrifugation, filtration and adjustment of solid content concentration are carried out to obtain a pigment dispersion.

The disperser used in the dispersion treatment of the pigment may be any disperser generally used, and examples thereof include a ball mill, a roll mill, a sand mill, a bead mill and a nanomizer. Among the above, a bead mill is preferably used, and specifically, it is commercially available under trade names such as a super mill, a sand grinder, an agitator mill, a grain mill, a dyno mill, a pearl mill and a cobol mill.

As a method of controlling the particle size distribution of the pigment dispersion, reducing the size of the grinding media of the dispersing machine mentioned above, changing the material of the grinding media, increasing the filling rate of the grinding media, the stirring member ( The shape of the agitator) may be changed, the dispersion treatment time may be lengthened, the dispersion treatment may be classified using a filter or a centrifuge, and combinations of these techniques may be mentioned. In order to keep the pigment in a suitable particle size range, the diameter of the grinding media of the above-mentioned disperser is preferably 0.1 to 3 mm. Further, as a material of the grinding media, glass, zircon, zirconia and titania are preferably used.

(2) Preparation of aqueous inkjet ink Then, the above-mentioned pigment dispersion is added with a water-soluble organic solvent, water and, if necessary, the binder resin mentioned above, surfactant and other additives, and stirred and mixed. . In addition, you may stir and mix, heating the said mixture in the range of 40-100 degreeC as needed.

(3) Removal of Coarse Particles The coarse particles contained in the above mixture are removed by a method such as filtration separation and centrifugation to obtain an aqueous inkjet ink. As a method of filtration separation, a known method can be used suitably. The pore size of the filter is not particularly limited as long as coarse particles and dust can be removed, but is preferably 0.3 to 5 μm, more preferably 0.5 to 3 μm. When filtration is performed, a filter may be used alone or in combination of two or more.

<Characteristics of aqueous inkjet ink>
The aqueous inkjet ink of the present embodiment has a viscosity of 3 to 20 mPa · s at 25 ° C.
It is preferable to adjust to Within this viscosity range, stable ejection characteristics are exhibited even from a typical inkjet head having a frequency of 4 to 10 KHz and an inkjet head having a high frequency of 10 to 70 KHz. In particular, by setting the viscosity at 25 ° C. to 4 to 10 mPa · s, it is possible to stably discharge 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 1 mL of ink using an E-type viscometer (TVE 25 L-type viscometer manufactured by Toki Sangyo Co., Ltd.).

In addition, the aqueous inkjet ink of the present embodiment is a water-based inkjet ink of the present embodiment, from the viewpoint that a printed material excellent in adhesion and image quality can be obtained when it is combined with the aqueous inkjet ink capable of stably discharging. The static surface tension at 25 ° C. is preferably 18 to 35 mN / m, more preferably 19 to 32 mN / m, and 20 to 30 mN / m.
m is particularly preferred. Further, from the viewpoint of preventing color mixing blur and color unevenness of the printed matter and obtaining a printed matter excellent in image quality, the type and amount of the water-soluble organic solvent and the surfactant are adjusted to obtain the aqueous ink of this embodiment. Preferably, the surface tension is equal to or less than the surface tension of the pretreatment liquid. The static surface tension in this embodiment can be measured in the same manner as in the case of the pretreatment liquid.

Also, for the same reason as above, the aqueous inkjet ink of the present embodiment is 25 ° C. · 10.
The dynamic surface tension in msec is preferably 25 to 40 mN / m, and 28 to 38
mN / m is more preferable, and 30 to 36 mN / m is particularly preferable. The dynamic surface tension in the present embodiment can be measured by the maximum bubble pressure method at 25 ° C. using a bubble pressure dynamic surface tension meter BP100 manufactured by Kruss.

In the aqueous inkjet ink of the present embodiment, the average secondary particle diameter (D50) of the pigment is preferably 40 nm to 500 nm, and more preferably 50 nm to 400 nm, in order to obtain a print having excellent color developability. Particularly preferably, it is 60 nm to 300 nm.
In order to keep the average secondary particle diameter within the above-mentioned preferred range, the pigment dispersion treatment step may be controlled as described above.
The average secondary particle size of the pigment can be measured by the same method as the particle size of the resin particles (A). In addition, when the said aqueous | water-based inkjet ink contains a resin particle as binder resin, it is preferable to produce the ink which substituted the quantity equivalent to the compounding quantity of the said resin particle to water, and to measure a particle diameter.

<Production method of printed matter>
Applying the pre-treatment liquid to a non-permeable substrate as a method of producing a printed matter in an embodiment of the ink set combining the pre-treatment liquid of the present embodiment and the aqueous inkjet ink; The step of applying the aqueous inkjet ink by one-pass inkjet printing to the portion on the porous substrate to which the pretreatment liquid has been applied, and drying the non-permeable substrate to which the aqueous inkjet ink is applied A method including the steps is preferably used. The above steps are preferably carried out in this order.

In the present specification, “one-pass inkjet printing” refers to a method in which an inkjet head is scanned only once with respect to a substrate being stopped, or printing is performed by passing the substrate only once under the fixed inkjet head. And the ink is not reprinted on the printed ink. However, in the case of scanning the ink jet head, it is necessary to adjust the discharge timing in consideration of the movement of the ink jet head, and the deviation of the landing position is likely to occur. Therefore, when printing the water-based ink of this embodiment, the method of passing a base material to the lower part of the fixed inkjet head is used preferably.

  Below, the manufacturing method of the printed matter using the ink set of this embodiment is demonstrated.

<Method of applying pretreatment liquid>
When producing a printed matter using the ink set of the present embodiment, preferably, the pretreatment liquid is applied onto the non-permeable substrate before printing the aqueous inkjet ink. As a method of applying the ink, either a method of printing without contact on the substrate like inkjet printing or a method of printing by bringing a pretreatment liquid into contact with the substrate may be adopted. In addition, when a printing method in which the pretreatment liquid is brought into contact is selected as a method for applying the pretreatment liquid, roller types such as an offset gravure coater, a gravure coater, a doctor coater, a bar coater, a blade coater, a flexo coater, and a roll coater are used. It can be used suitably.

<Drying method after application of pretreatment liquid>
In the ink set of the present embodiment, after applying the pretreatment liquid to the non-permeable substrate, the non-permeable substrate is dried, and after the pretreatment liquid on the substrate is dried, the aqueous inkjet ink is The aqueous inkjet ink may be applied before the pretreatment liquid on the substrate is completely dried. In one embodiment, it is preferable to completely dry the pretreatment solution before applying the aqueous inkjet ink, that is, to substantially remove the liquid component of the pretreatment solution. By applying the aqueous inkjet ink after the pretreatment liquid is completely dried, it is possible to obtain a print excellent in abrasion resistance without causing a drying defect in the aqueous inkjet ink to be landed later.

There is no particular limitation on the drying method used for printing the pretreatment liquid of the present embodiment, and for example, conventionally known methods such as heat drying, hot air drying, infrared drying, microwave drying, drum drying, etc. may be mentioned. Can. The above-mentioned drying method may be used alone or in combination of two or more, but in order to reduce damage to the non-permeable substrate and to dry efficiently, it is preferable to use a hot air drying method. Also, from the viewpoint of preventing damage to the substrate and bumping of the liquid component in the pretreatment liquid, in the case of employing the heat drying method, the drying temperature is set to 35 to 100 ° C., and the hot air drying method is also adopted. In the case, it is preferable to set the hot air temperature to 50 to 150 ° C.

<Method of applying aqueous ink jet ink>
The aqueous inkjet ink is preferably applied to the portion of the non-permeable substrate to which the pretreatment liquid has been applied by one-pass inkjet printing. The design resolution of the ink jet head used in the one-pass ink jet printing is preferably 600 dpi (DotsPerInch) or higher, from the viewpoint of obtaining an image excellent in image quality, and 720 dpi
It is more preferable that it is more than.

<Drying method after aqueous ink jet ink printing>
After printing the aqueous inkjet ink, it is preferable to include the step of drying the non-permeable substrate to which the aqueous inkjet ink has been applied in order to dry the aqueous ink and the undried pretreatment liquid. In addition, the drying method suitably used is the same as that of the case of the said pre-processing liquid.

<Pre-treatment liquid and application amount of aqueous inkjet ink>
When printing the ink set of the present embodiment, it is preferable to set the ratio of the application amount of the aqueous inkjet ink to the application amount of the pretreatment liquid to 0.1 or more and 10 or less. The ratio of the application amount is more preferably 0.5 or more and 9 or less, and particularly preferably 1 or more and 8 or less. By setting the ratio of the application amount within the above range, a printed matter having excellent image quality can be obtained without causing a change in the feel of the substrate.

<Non-permeable substrate>
As the non-permeable substrate using the ink set of the present embodiment, conventionally known ones can be optionally used. For example, polyvinyl chloride sheet, polyethylene terephthalate (PET
Thermoplastic resin substrates such as films, polypropylene films, polyethylene films, nylon films, polystyrene films, polyvinyl alcohol films, and metal substrates such as aluminum foil. The above-mentioned substrate may be smooth or uneven, or may be transparent, semi-transparent or opaque. Further, two or more of these base materials may be pasted together. Furthermore, a release adhesive layer may be provided on the opposite side of the printing surface, and after printing, an adhesive layer may be provided on the printing surface. The shape of the substrate used for printing the ink set of the present embodiment may be in the form of a roll or sheet.

Among them, it is preferable that the non-permeable substrate is a thermoplastic resin substrate, in order to sufficiently express the function of the pretreatment liquid of the present embodiment, that it is a PET film, a polypropylene film, a polyethylene film, or a nylon film. Is particularly preferred.

Moreover, from the viewpoint of applying the pretreatment liquid of the present embodiment uniformly and uniformly and improving the adhesion, the surface modification method such as corona treatment or plasma treatment is applied to the non-permeable substrate exemplified above. It is also preferable to apply

<Coating treatment>
The printed matter produced using the ink set of the present embodiment can be coated on the printing surface, if necessary. Specific examples of the coating treatment include coating / coating of a coating composition, lamination by a dry lamination method, a solventless lamination method, an extrusion lamination method, etc. You may combine them.

In addition, when coating-processing to a printed matter by coating and printing the composition for coating, the system and non-contact printing method with respect to a base material like inkjet printing as a coating-printing method, and a base material On the other hand, any of the methods of printing with the coating composition in contact may be employed. In addition, when the method of printing a coating composition on a substrate without contact is selected, a colorant component substantially excluding the pigment from the aqueous inkjet ink of the present embodiment is used as the coating composition. It is preferred to use an ink (clear ink) which is not contained.

In addition, when the printed matter is to be laminated, the adhesive used to laminate the sealant substrate is preferably composed of a mixture of a polyol component and a polyisocyanate component.

The polyol component is a resin component having a hydroxyl group, and a polyurethane resin or a polyester resin is preferably used in view of coatability, wettability and permeability to the printed material interface, and laminate strength developed after aging. Above all, the wettability to the interface of the printed matter obtained by the ink set of this embodiment, for example, the printing layer (printed portion) and the pretreatment liquid layer (non-printed portion) is good, and the laminated printed matter (laminate) It is preferable that a polyol component contains polyester polyol from the point which is excellent also in the lamination strength of this. The polyol component may be a single component or a combination of multiple components.

The polyisocyanate component reacts with the polyol component to form a urethane bond, thereby increasing the molecular weight of the adhesive layer and improving the laminate strength. Among them, the polyisocyanate component is an isocyanate from the viewpoint of compatibility with the polyol component, wettability to the interface of the printed material obtained by the ink set of the present embodiment, and laminate strength of the laminated printed product (laminate). It is preferable to contain the polyether terminal urethane resin of a group terminal. From the same viewpoint as above, the blending amount of the polyisocyanate component is preferably 50 to 80% by mass with respect to the polyol component. The polyisocyanate component may be a single component, or a plurality of components may be used in combination.

In addition, as a sealant base material used for the said lamination process, polypropylene films and polyethylene films, such as an axiaxially-stretched polypropylene (CPP) film and a linear short chain branched polyethylene (LLDPE) film, can be illustrated. Moreover, you may use the film in which metal (oxide) vapor deposition layers, such as aluminum oxide, were formed.

Hereinafter, the pretreatment liquid which is an embodiment of the present invention and an ink set containing the pretreatment liquid and an aqueous inkjet ink will be described in more detail with reference to Examples and Comparative Examples. In the following description, “parts” and “%” are “parts by mass” unless otherwise specified.
, Represents "mass%".

<Production Example of Thickener 1>
After 300 parts of polyethylene glycol having a number average molecular weight of 4,000 were dehydrated at 80 to 90 ° C. under reduced pressure for 3 hours, 14 parts of hexamethylene diisocyanate was added and reacted at 80 to 90 ° C. for 5 hours. Further, 2.8 parts of 1-eicosanol was added and reacted at 80 to 90 ° C. for 3 hours, and ion exchanged water was added to obtain a 30% aqueous solution of Thickener 1. In the above-mentioned general formula (3), R ₁ and R ₄ are eicosyl groups (carbon number 20), R ₂ and R ₃ are hexamethylene groups (carbon number 6), and A _{1 to} A ₄ are It was a hydrophobically modified water-soluble urethane resin having all urethane bonds, l = 90 and m = 25.

<Production Example of Thickener 2>
After dehydrating 280 parts of polyethylene glycol having a number average molecular weight of 4,000 at 80 to 90 ° C. for 3 hours under reduced pressure, 13 parts of hexamethylene diisocyanate is added, and 30 at 80 to 90 ° C.
I was allowed to react for a minute. Further, 19 parts of 1-octadecanol was added and reacted at 80 to 90 ° C. for 3 hours, and then ion exchanged water was added to obtain a 30% aqueous solution of Thickener 2. In General Formula (3), R ₁ and R ₄ are octadecyl group (18 carbon atoms), R ₂ and R ₃ are hexamethylene group (6 carbon atoms), and A _{1 to} A ₄ are All urethane bonds were hydrophobic modified water-soluble urethane resins in which l = 90 and m = 2.

<Production Example of Thickener 3>
After 280 parts of polyethylene glycol having a number average molecular weight of 4,000 were dehydrated at 80 to 90 ° C. for 3 hours under reduced pressure, 18 parts of hexamethylene diisocyanate was added and reacted at 80 to 90 ° C. for 4 hours. Further, 2.8 parts of 1-eicosanol was added and reacted at 80 to 90 ° C. for 3 hours, and then ion exchanged water was added to obtain a 30% aqueous solution of thickener 3. In addition, in the above-mentioned general formula (3), R ₁ and R ₄ represent an ekikosyl group, R ₂ and R ₃ represent a hexamethylene group (having 6 carbon atoms), and all of A _{1 to} A ₄ represent a urethane bond in the general formula (3) It was a hydrophobic modified water-soluble urethane resin of = 90 and m = 21.

<Production Example of Thickener 4>
After 280 parts of polyethylene glycol having a number average molecular weight of 4,000 were dehydrated at 80 to 90 ° C. under reduced pressure for 3 hours, 16 parts of hexamethylene diisocyanate was added and reacted at 80 to 90 ° C. for 3 hours. Further, 2.8 parts of 1-eicosanol was added, reacted at 80 to 90 ° C. for 3 hours, and ion exchanged water was added to obtain a 30% aqueous solution of thickener 4. In the above-mentioned general formula (3), in the thickener 4, R ₁ and R ₄ are an ekikosyl group, R ₂ and R ₃ are hexamethylene groups (having 6 carbon atoms), and all of A _{1 to} A ₄ are urethane bonds, l It was a hydrophobic modified water-soluble urethane resin of = 90 and m = 18.

<Production Example of Thickener 5>
After 390 parts of polyethylene glycol having a number average molecular weight of 4,000 were dehydrated under reduced pressure at 80 to 90 ° C. for 3 hours, 18 parts of hexamethylene diisocyanate was added and reacted at 80 to 90 ° C. for 4 hours. Further, 40 parts of Steareth-40 (polyoxyethylene stearyl ether having 40 moles of ethylene oxide group) is added and reacted at 80 to 90 ° C. for 3 hours, and then ion-exchanged water is added to obtain 30 of thickener 5. % Aqueous solution was obtained. In the above-mentioned general formula (4), the thickener 5 has R ₅ and R ₈ as octadecyl group (18 carbon atoms), R ₆ and R ₇ as hexamethylene group (6 carbon atoms), and A _{5 to} A ₈ All urethane bonds, n = 40, o = 90, p = 10,
It was a hydrophobically modified water-soluble urethane resin of q = 40.

<Production Example of Pretreatment Liquid 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 mixed for an additional hour. Then, after cooling the mixture to room temperature,
Pretreatment liquid 1 was obtained by filtration through a membrane filter with a pore size of 1 μm. In addition, about the detail of the material used below, it described in Tables 2-3 mentioned later.
-Joncryl 7100 (solid content 48%) 10.4 parts-Aluminum sulfate 5.0 parts-Adecanol UH-540 3.3 parts-Surfynol 465 0.5 parts-Proxel GXL 0.1 parts-2-propanol ( 2 PrOH) 5.0 parts · Ion-exchanged water 75.7 parts

<Production Example of Pretreatment Solutions 2 to 114>
Pretreatment solutions 2 to 1 were prepared in the same manner as pretreatment solution 1 except that the materials listed in Table 1 were used.
14 was manufactured.

The details of the materials listed in Table 1 are as shown in Tables 2-3 below. In Tables 2 and 3, the melting point is 50% by differential scanning calorimetry using “DSC-60 Plus” manufactured by Shimadzu Corporation.
The particle size is a value measured by a dynamic light scattering method using Microtrack UPAEX-150 manufactured by Microtrack Bell.

<Measurement of Moisture Absorption Mass Increase Rate of Flocculant (B)>
In addition, in Table 2, the moisture absorption mass increase rate of the material used as a coagulant | flocculant (B) was shown based on the following reference | standard. Here, the moisture absorption mass increase rate was measured by the method described above, 40 ° C., 80%
It is a mass increase rate of the coagulant | flocculant (B) stored for 24 hours in RH environment.
A: Moisture absorption increase rate was 40% by mass or less B: Moisture absorption increase rate was more than 40% by mass and 75 wt% or less C: Moisture absorption increase rate was greater than 75% by mass

[Examples 1 to 94, Comparative Examples 1 to 20]
The following evaluation was implemented about the pre-processing liquids 1 to 114 manufactured above. The evaluation results are as shown in Table 4.

<Evaluation of storage stability of pretreatment liquid>
The viscosity of the pre-treatment solution manufactured above was measured using an E-type viscometer (TVE-20L manufactured by Toki Sangyo Co., Ltd.) under an environment of 25 ° C., and then placed in a closed container, and the inside of a thermostatic chamber set at 50 ° C. It kept still. The sealed container was taken out every week, the viscosity after aging was measured in the same manner as described above, and the viscosity change rate before and after aging was calculated to evaluate the storage stability of the pretreatment liquid. Evaluation criteria were as follows, and AA, A, and B were practically usable.
AA: Viscosity change rate after 4 weeks storage was less than ± 5% A: Viscosity change rate after 3 weeks storage was less than ± 5%, Viscosity change rate after 4 weeks storage was ± 5% B: The viscosity change rate after 2 weeks storage was less than ± 5%, but the viscosity change rate after 3 weeks storage was ± 5% or more C: Viscosity change rate after 1 week storage Was less than ± 5%, but the viscosity change rate after 2 weeks storage was ± 5% or more D: The viscosity change rate after 1 week storage was ± 5% or more

<Example of preparation of film substrate to which pretreatment liquid has been applied>
About the pretreatment liquid manufactured above, K Control Coater K202 by Matsuo Sangyo Co., Ltd. wire bar No. The film substrate coated with the above pretreatment solution is applied at 70 ° C. after applying the pretreatment solution prepared above to a wet film thickness of 4.0 ± 0.2 μm on the following film substrate using 0.
The film base to which the pre-processing liquid was provided was produced by putting into an air oven and drying for 3 minutes.

<Film base used for evaluation>
-OPP: A biaxially stretched polypropylene film "OPU-1" manufactured by Mitsui Chemicals Totoro Co., Ltd. (thickness 20 μm)
-PET: polyethylene terephthalate film "FE 2001" (12 μm in thickness) manufactured by Futamura Co., Ltd.

<Evaluation of coating unevenness of pretreatment liquid>
Based on the above method, the appearance of the pretreatment liquid applied to the OPP film substrate was observed visually and with a loupe. Evaluation criteria were as follows, and AA, A, and B were practically usable.
AA: No haze or coating unevenness was observed visually or with a loupe A: Coating unevenness was slightly observed with a loupe, but no haze or coating unevenness was observed visually B: Hauge with a loupe And coating unevenness was slightly observed, but no repelling or coating unevenness was visually observed C: repelling or coating unevenness was slightly observed visually D: repelling or coating unevenness visually Clearly seen

<Production of aqueous inkjet ink>
<Production Example of Resin 1 for Pigment Dispersion>
In a reaction vessel equipped with a gas introduction tube, a thermometer, a condenser, and a stirrer, 95 parts of butanol was charged and replaced with nitrogen gas. The reaction vessel is heated to 110 ° C., and a mixture of 45 parts of styrene, 30 parts of acrylic acid, 25 parts of lauryl methacrylate as a polymerizable monomer, and 6 parts of V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) as a polymerization initiator It dripped over 2 hours and the polymerization reaction was performed. After completion of the dropwise addition, the mixture is reacted at 110 ° C. for 3 hours, and 0.6 parts of V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) is added,
The reaction was further continued at 110 ° C. for 1 hour to obtain a solution of resin 1 for pigment dispersion. Furthermore, after cooling to room temperature, dimethylaminoethanol was added to completely neutralize it, and then 100 parts of water was added to make it aqueous. Thereafter, the temperature is raised to 100 ° C. or more, butanol is azeotroped with water to distill off butanol, and the solid content is adjusted to 30% to obtain an aqueous solution of pigment dispersing resin 1 (solid content 30 %) Got. The acid value of resin for pigment dispersion 1 measured by the method described above was 230 mg KOH / g, and the weight average molecular weight was 25,000.

<Production example of aqueous solution of pigment dispersion resins 2 to 7>
As shown in Table 5 below, aqueous solution of pigment dispersing resins 2 to 7 (solid content) in the same manner as in the case of pigment dispersing resin 1 except that the type and amount of the polymerizable monomer were changed. 30%).

<Production Example of pigment dispersion 1C, 1M, 1Y, 1K>
Toyo Color LIONOL BLUE 7358G (CI Pigment Blue 1
20 parts of 5: 3), 20 parts of an aqueous solution of pigment dispersing resin 1 (solid content 30%), and 60 parts of water are mixed and premixed with a stirrer, and then zirconia beads of diameter 0.5 mm 1800
The main dispersion was performed using a Dino mill with a volume of 0.6 L filled with g to obtain a pigment dispersion liquid 1C. Also, the above-mentioned C.I. I. Pigment dispersions 1M, 1Y, and 1K were obtained in the same manner as in pigment dispersion 1C, except that pigment blue 15: 3 was replaced with the pigments shown below, respectively.
Magenta: DIC's FASTGEN SUPER MAGENTA RG
(CI Pigment Red 122)
Yellow: Toyo Color LIONOL YELLOW TT1405G
(CI Pigment Yellow 14)
-Black: Printe X 85 manufactured by Orion Engineered Carbons
(Carbon black)

<Production Example of Pigment Dispersions 2 to 7 (C, M, Y, K)>
Pigment dispersion by using the same method as pigment dispersions 1C, 1M, 1Y, and 1K except that an aqueous solution (30% solid content) of pigment dispersion resins 2 to 7 is used as a pigment dispersion resin 2
To 7 (C, M, Y, K, respectively) were obtained.

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

<Production Example of Aqueous Inkjet Ink Set 1 (CMYK)>
The following materials were sequentially introduced into a mixing vessel equipped with a stirrer, and stirred until sufficiently uniform. Then, filtration was performed using a membrane filter with a pore size of 1 μm to remove coarse particles that cause clogging of the inkjet head, whereby an aqueous inkjet cyan ink 1 was obtained.
Further, by using pigment dispersions 1M, 1Y and 1K instead of pigment dispersion 1C, an aqueous inkjet ink comprising four colors of cyan (C), magenta (M) yellow (Y) and black (K) I got a set of one.
Pigment dispersion 1C 25 parts Joncryl 8211 (solid content 44%) 15 parts 1,2-propanediol 20 parts KF-6015 1 part Proxel GXL 0.1 part Ion-exchanged water 38.9 parts

In the above production example, Joncryl 8211 is a BASF acrylic resin emulsion (solid content 44%).

<Production Example of Inkjet Ink Sets 2 to 26 (CMYK)>
Set 2 of inkjet ink consisting of four colors of cyan (C), magenta (M) yellow (Y) and black (K) by the same method as inkjet ink set 1 except using the materials described in Table 6 I got ~ 26.

In Table 6, Caboj shown below in Inkjet ink set 8
The blending amounts of C, M and Y are 50% by mass and K is 25% by mass, and the blending amounts of ion-exchanged water are C, M and Y 13.9% by mass, and K is 38.9%. %. Moreover, the abbreviation and details of materials not listed in Tables 2 to 3 among the materials listed in Table 6 are as follows.

-CaboJet:
Cyan: Cabojet 250C (Cabot self-dispersed cyan pigment water soluble
Solution, pigment concentration 10%)
Magenta: Cabojet 265M (Mabbot self-dispersing magenta
Pigment aqueous solution, pigment concentration 10%)
Yellow: Cabojet 270 (Cabot-made self-dispersing yellow pigment
Aqueous solution, pigment concentration 10%)
Black: Cabojet 200 (Cabot self-dispersed carbon black
Aqueous solution, pigment concentration 20%)
・ PGmME: Propylene glycol monomethyl ether (boiling point 1 under 1 atmosphere)
20 ° C)
1,2-BD: 1,2-butanediol (boiling point 192 ° C. at 1 atm)
1,2-HD: 1,2-hexanediol (boiling point 224 ° C. at 1 atm)
-TEGmEE: triethylene glycol monoethyl ether (boiling point 256 ° C under 1 atmosphere)
・ KF-6015: Siloxane based surfactant manufactured by Nisshin Chemical Industry Co., Ltd.

In Table 6, the water-soluble organic solvents contained in each ink have a weighted boiling point average value (° C.) under 1 atmosphere and a water-soluble organic solvent having a boiling point of 250 ° C. (or 220 ° C.) or more under 1 atmosphere. The amount of solvent (% by mass) is also described.

<Production Example of Aqueous Inkjet White Ink 1 to 11>
Aqueous inkjet white inks 1 to 11 were obtained by the same method as inkjet cyan ink 1 except that the materials listed in Table 7 below were used.

<Production example of printed matter>
An inkjet head KJ4B-QA (manufactured by KYOCERA, design resolution 600 dpi) is installed on the upper part of a conveyor capable of transporting a substrate, and the set of aqueous inkjet ink manufactured above is ordered from K, C, M, Y from the upstream side It was filled in. Next, after fixing the film base material to which the pretreatment liquid has been applied and produced above is fixed on the conveyor, the conveyor is driven at a constant speed, and the inkjet ink is moved when passing through the installation portion of the inkjet head. The respective images were discharged using a drop volume of 10 pL, and the following images were printed. Immediately after printing,
The printed matter was placed in a 70 ° C. air oven and dried for 3 minutes to produce a printed matter.

The conveyor drive speed was 25 m / min, 50 m / min, and 75 m / min under three conditions, and printing was performed respectively. Also, as a print image, an image in which a 100% solid patch of 5 cm × 5 cm printing rate is adjacent in the order of CMYK (hereinafter referred to as “solid patch image”), a total printing rate (
A four-color (CMYK) image (the sum of the printing rate of each color) is continuously changed from 40 to 320%
Hereinafter, it is called "gradation image". The printing ratio of each color in each total printing ratio is the same, and a solid image with a total printing ratio of 320% using CMYK (hereinafter referred to as "4C solid image". The printing ratio of each color is All were prepared 80%, and 3 types of were prepared, and each printed matter was produced.

[Examples 95 to 213, Comparative Examples 21 to 40]
The combination of the pretreatment liquid and the set of aqueous inkjet ink shown in Table 8 below
The above printed matter was produced. The following evaluation was performed using this printed matter or the pretreatment liquid itself. The evaluation results are as shown in Table 8.

<Evaluation of image quality>
A gradation image print on an OPP film substrate was used based on the above method, created at 25 m / min or 50 m / min, 75 m / min conveyor drive speed conditions. The image quality (color mixing blur or color unevenness) was evaluated by observing the dot shape of the image printed matter at 200 × using an optical microscope. Evaluation criteria were as follows, and AA, A, and B were practically usable.
AA: 75 m / min did not show any color mixing blur or color unevenness A: 75 m / min showed some color mixing blur or color unevenness, but 50 m / min showed no color mixing blur or color blur B Color mixing blur or color unevenness was slightly observed at 50 m / min, but color mixing blur or color unevenness was not observed at 25 m / min. C: color mixing blur or color unevenness was observed at 25 m / min

<Evaluation of adhesion>
Based on the above method, a solid patch image print made at a conveyor driving speed condition of 50 m / min was used. A cellophane tape (18 mm in width) manufactured by Nichiban Co., Ltd. was firmly attached to the surface of the printed image, and the tip of the cellophane tape was held and peeled off while maintaining an angle of 90 degrees. Then, the adhesion was evaluated by visually checking the surface of the printed matter after peeling and the cellophane tape surface. The evaluation criteria were as follows, and AA, A, and B were practically possible. The adhesion was evaluated for both the printed matter on the OPP film substrate and the printed matter on the PET film substrate. Further, in Table 8, among the four colors evaluated, the color with the worst evaluation result is described.
AA: The peeling area of the cellophane tape to the adhesive surface was less than 5%. A: The peeling area of the cellophane tape to the adhesive surface was less than 5-10%. B: The peeling area of the cellophane tape to the adhesive surface was 10% or more. Less than 20% C: Peeling area to adhesive surface of cellophane tape was 20% or more and less than 30% D: Peeling area to adhesive surface of cellophane tape was 30% or more

<Evaluation of dryness>
A solid patch image was printed on the OPP film substrate to which the pretreatment liquid was applied under the condition of a conveyor driving speed of 50 m / min in the same manner as in the production example of the above printed matter. Immediately after printing, the printed matter was put into an air oven at 70 ° C., and then the printed matter was taken out from the air oven every minute, and the surface was rubbed with a finger to evaluate the drying property by visual observation. Evaluation criteria were as follows, and AA, A, and B were practically usable.
AA: The printed matter was dried 1 minute after the air oven was inserted, and the ink did not adhere even when rubbed with a finger. A: The ink was adhered to the finger one minute after the air oven was inserted, but after 2 minutes No adhesion B: The ink adhered to the finger two minutes after the air oven was turned on, but not three minutes later C: The ink adhered to the finger even in the printed matter three minutes after the air oven was turned on did

<Evaluation of blocking resistance>
Based on the above method, a 4C solid image print on an OPP film substrate was used, made at a conveyor driving speed condition of 50 m / min. The image printed matter was cut into a 4 cm × 4 cm square, superposed on the back of the same OPP film as that used for printing, and subjected to a blocking test using a permanent strain tester. The environmental conditions of the blocking test are a load of 10 kg / cm
^{2. The} temperature was 40 ° C., the humidity was 80%, and the test period was 24 hours. After 24 hours, while keeping the angle of 90 degrees, the stacked OPP films were instantaneously pulled off, and the printed surface after peeling was visually confirmed to evaluate the blocking resistance. Evaluation criteria are as follows, AA,
A and B are practically usable.
AA: The peeling area of the printing surface was less than 5% A: The peeling area of the printing surface was 5% or more and less than 10% B: The peeling area of the printing surface was 10% or more and less than 15% C: Peeling area of printed surface was 15% or more

[Examples 214 to 227]
Moreover, about the combination of the pre-processing liquid, the aqueous inkjet black ink (The black thing of the set of aqueous inkjet ink), and the aqueous inkjet white ink shown in the following Table 9, clear and visible by the method shown below Evaluation was also conducted. The evaluation results were as shown in Table 9.

<Evaluation of sharpness and visibility>
The ink jet head KJ4B-QA was installed on the upper part of the conveyor which can convey the substrate, and the colors of the aqueous inkjet black ink (K ink) and the aqueous inkjet white ink (W ink) shown in Table 9 were described in Table 9 It was filled as it was on the upstream side.
However, in Example 227, only the K ink was used without using the W ink. Next, after fixing the film base material to which the pretreatment liquid has been applied shown in Table 9 on the conveyor, the conveyor is driven at a speed of 50 m / min to pass through the installation portion of the inkjet head And the above-mentioned aqueous inkjet ink were respectively discharged. At that time, for K ink,
For the W ink, a white solid image with a 100% printing rate was printed. Also, the image by the ink filled downstream was printed so as to be superimposed on the image by the ink filled upstream. Then, immediately after printing, the printed matter was put into a 70 ° C. air oven and dried for 3 minutes to create a character / white solid printed matter.
The obtained character / white solid printed matter was visually observed from the observation surface described in Table 9 to evaluate the sharpness and visibility. The evaluation criteria were as follows, and AA, A, and B were practically possible.
AA: The characters of 4 points and 6 points were clear and clearly readable.
A: The four-point character was somewhat less clear, but was sufficiently readable, and the six-point character was clear and clearly readable.
B: The four-point character was too sharp to read. On the other hand, the six-point character was somewhat less clear, but it was readable enough.
C: The letters of 4 points and 6 points were too sharp to read.

The pretreatment solutions 95 to 97 described in Table 1 are systems using resin particles that are not resin particles (A), and the pretreatment solutions 98 to 99 and 109 are systems using flocculants that are not flocculants (B), Pretreatment solution 10
0 to 104 is a system using a thickener which is not the thickener (C), the pretreatment liquid 114 is a thickener (
Although it is a system which does not include C), it has not reached the practicable level in all the items evaluated. In addition, pretreatment solutions 105 to 108 use a surfactant having an HLB value of more than 13.5, pretreatment solution 110 does not contain resin particles, and pretreatment solution 113 uses a surfactant. It is a system that did not do it. As a result of the evaluation, although the storage stability of the pretreatment liquid was good, unevenness occurred at the time of coating, and as a result, deterioration of the image quality and adhesion, and further the drying property and blocking resistance were observed.

The pretreatment liquid 111 described in Table 1 is a reproduction of the reaction liquid 8 described in Patent Document 5 (Japanese Patent Laid-Open No. 2018-1625), and the pretreatment liquid 112 is a compound disclosed in Japanese Patent Application Laid-Open No. 2017-2006. 1
09411 gazette) is reproduced. As a result of evaluation, unevenness occurred at the time of coating, and as a result, deterioration in image quality and adhesion was observed. Furthermore, the deterioration of blocking which is considered to be caused by the moisture absorption of the coagulant was also observed, and the quality did not reach practical use.

In contrast to the above, in the pretreatment solutions 1 to 94 simultaneously containing the resin particles (A), the coagulant (B), the thickener (C) and the surfactant (D), all items evaluated It was confirmed that the quality was more than practicable. If this result is missing even one of the above components,
The effects of the present invention, in particular, the unevenness at the time of coating can not be suppressed, and as a result, it is shown that the deterioration of the image quality and the adhesion occurs.

Claims (8)

A pretreatment liquid for use with an aqueous inkjet ink comprising a pigment and water,
The pretreatment liquid comprises resin particles (A), a coagulant (B), a thickener (C) and a surfactant (D).
) And water,
The 50% particle diameter (D50) of the resin particles (A) is 30 to 350 nm,
The coagulant (B) contains at least one selected from the group consisting of polyvalent metal salts and cationic polymer compounds,
The moisture absorption rate at 80% relative humidity of the coagulant (B) is 75% by mass or less,
The thickener (C) contains a hydrophobically modified water-soluble urethane resin,
The pretreatment liquid whose HLB value of the said surfactant (D) is 13.5 or less.   The pretreatment liquid according to claim 1, wherein the resin particles (A) are polyolefin resin particles. The pretreatment liquid according to claim 1 or 2, wherein the HLB value of the surfactant (D) is 1.0 to 8.5. The pretreatment liquid according to any one of claims 1 to 3, wherein the coagulant (B) contains a divalent metal salt as the polyvalent metal salt. The compounding quantity of the said thickener (C) is 1-100 mass% with respect to the compounding quantity of the said resin particle (A)
The pretreatment liquid according to any one of claims 1 to 4, which is The pretreatment liquid according to any one of claims 1 to 5, further comprising a water-soluble organic solvent having a static surface tension of 20 to 40 mN / m at 25 ° C. The pretreatment liquid according to any one of claims 1 to 6,
An ink set comprising a pigment, a water soluble organic solvent, and an aqueous inkjet ink comprising water. The printed matter in which the said aqueous | water-based inkjet ink is printed on the base material which provided the pre-processing liquid in any one of Claims 1-6.