WO2022044985A1

WO2022044985A1 - Pretreatment liquid for impermeable base materials, and ink set

Info

Publication number: WO2022044985A1
Application number: PCT/JP2021/030522
Authority: WO
Inventors: 俊博仮屋; 健志宮戸
Original assignee: 富士フイルム株式会社
Priority date: 2020-08-27
Filing date: 2021-08-20
Publication date: 2022-03-03
Also published as: JPWO2022044985A1; JP7371265B2

Abstract

The present invention provides: a pretreatment liquid for impermeable base materials, said pretreatment liquid enabling the production of an image recorded material or a record-receiving medium which is suppressed in the occurrence of a precipitate and the occurrence of blocking; an ink set; an image recording method; an image recorded material; a record-receiving medium; and a method for producing a record-receiving medium. This pretreatment liquid for impermeable base materials contains water and three or more kinds of carboxylic acids; and the content of carboxylic acids having a ClogP of less than -1.00 is 2.0% by mass or less relative to the total amount of this pretreatment liquid for impermeable base materials.

Description

Pretreatment liquid for impermeable substrate, ink set, image recording method, image recording material, recording medium and method for manufacturing the same.

The present disclosure relates to a pretreatment liquid for a non-permeable substrate, an ink set, an image recording method, an image recording material, a recording medium, and a method for manufacturing the same.

Conventionally, regarding image recording on a non-permeable substrate such as a plastic film, a technique for recording an image using ink and a pretreatment liquid has been known. The pretreatment liquid is also referred to as a precoat liquid.
For example, Patent Document 1 describes a precoat agent used for forming a precoat layer that receives an ink that forms an image by an inkjet method, and is water, a cationic resin having a polyurethane structure, or two or more identical functional groups. A precoating agent comprising an organic acid having a group and a cross-linking agent capable of reacting with the functional group is disclosed. The precoating agent described in Patent Document 1 was formed on a non-absorbable recording medium such as nylon (Ny), polyethylene terephthalate (PET), polypropylene (PP, particularly OPP) regardless of the material of the recording medium. The purpose is to have high durability of the coating film and the image formed thereafter, and to improve the image quality of the formed image.
Further, Patent Document 2 describes as a pretreatment liquid for a non-permeable substrate that suppresses transfer of components contained in the pretreatment liquid from the image recording surface to a non-contact body and obtains a fine image. A polyvalent carboxylic acid containing water, a resin, and an organic acid, the ratio of the content of the resin to the content of the organic acid is more than 0 and less than 4 on a mass basis, and the organic acid has a specific structure. The pretreatment liquid for a non-permeable substrate is disclosed.

International Publication No. 2017/013984 International Publication No. 2019/235141

However, when an image recording material or a recording medium is produced using a pretreatment liquid containing water and a carboxylic acid, precipitates may be generated in the obtained image recording material or the recording medium. The precipitate is considered to be a precipitate of carboxylic acid.
As a method for suppressing the generation of precipitates, a method using a highly hydrophilic (that is, low ClogP) carboxylic acid as the carboxylic acid in the pretreatment liquid can be considered. However, by the study of the present inventors, it has been found that in the case of this method, blocking may occur in the obtained image recording material or the recorded medium.

An object of one aspect of the present disclosure is a pretreatment liquid for a non-permeable substrate, an ink set, and an image capable of producing an image recording material or a recording medium in which the generation of precipitates and the generation of blocking are suppressed. It is an object of the present invention to provide a recording method, and an image recording material and a recording medium in which the generation and blocking of precipitates are suppressed.

Specific means for solving the problem include the following aspects.
<1> A pretreatment liquid for a non-permeable substrate containing water and three or more kinds of carboxylic acids.
A pretreatment liquid for a non-permeable substrate in which the content of the carboxylic acid having a Clog P of less than −1.00 is 2.0% by mass or less based on the total amount of the pretreatment liquid for a non-permeable substrate.
<2> The non-permeation according to <1>, wherein the total content of three or more kinds of carboxylic acids is 5.0% by mass to 13.0% by mass with respect to the total amount of the pretreatment liquid for a non-permeable substrate. Pretreatment liquid for sex substrates.
<3> The pretreatment liquid for a non-permeable substrate according to <1> or <2>, wherein the weight average ClogP of three or more kinds of carboxylic acids is 0.50 or less.
<4> The pretreatment liquid for a non-permeable substrate according to any one of <1> to <3>, wherein the weight average ClogP of three or more kinds of carboxylic acids is −1.00 or more.
<5> The pretreatment liquid for a non-permeable substrate according to any one of <1> to <4>, wherein the three or more kinds of carboxylic acids contain two or more kinds of polyvalent carboxylic acids.
<6> Three or more kinds of carboxylic acids
Polyvalent carboxylic acid A1, which is a polyvalent carboxylic acid having a ClogP of -1.00 or more and less than -0.50, and
Polyvalent carboxylic acid A2, which is a polyvalent carboxylic acid having a ClogP of -0.50 or more and -0.10 or less,
Polyvalent carboxylic acid A3, which is a polyvalent carboxylic acid having a ClogP of more than -0.10 and 0.50 or less,
The pretreatment liquid for a non-permeable substrate according to any one of <1> to <5>.
<7> The content mass of the polyvalent carboxylic acid A1, which is a polyvalent carboxylic acid having a ClogP of -1.00 or more and less than -0.50, is defined as [A1].
The content mass of the polyvalent carboxylic acid A2, which is a polyvalent carboxylic acid having a ClogP of -0.50 or more and -0.10 or less, is defined as [A2].
When the content mass of the polyvalent carboxylic acid A3, which is a polyvalent carboxylic acid having a ClogP of more than -0.10 and 0.50 or less, is set to [A3].
The pretreatment liquid for a non-permeable substrate according to any one of <1> to <6>, wherein the [A2] / ([A1] + [A3]) ratio is 0.5 to 5.0.
<8> The pretreatment liquid for a non-permeable substrate according to any one of <1> to <7>, which further contains a resin.
<9> The pretreatment liquid for a non-permeable substrate according to <8>, wherein the resin contains resin particles.
<10> The pretreatment liquid for a non-permeable substrate according to any one of <1> to <9>,
Inks containing water and colorants,
Ink set with.
<11> A step of applying the pretreatment liquid for a non-permeable substrate according to any one of <1> to <9> on the impermeable substrate to form a layer.
A process of applying an ink containing a colorant and water to a part of the layer to record an image,
Image recording method having.
<12> Non-permeable base material and
A layer arranged on the impermeable substrate and formed by the pretreatment liquid for the impermeable substrate according to any one of <1> to <9>.
An image containing a colorant placed partly on the layer,
Image recordings provided with.
<13> A recording medium having a step of applying the pretreatment liquid for a non-permeable substrate according to any one of <1> to <9> on the impermeable substrate to form a layer. Production method.
<14> Non-permeable base material and
A layer arranged on the impermeable substrate and formed by the pretreatment liquid for the impermeable substrate according to any one of <1> to <9>.
A recording medium comprising.

According to one aspect of the present disclosure, a pretreatment liquid for a non-permeable substrate, an ink set, and an image capable of producing an image recording material or a recording medium in which the generation of precipitates and the generation of blocking are suppressed. A recording method and an image recording material and a recording medium in which the generation and blocking of precipitates are suppressed are provided.

It is a schematic block diagram which shows an example of the image recording apparatus suitable for carrying out the image recording method which concerns on one example of this disclosure. It is a figure which conceptually shows the character image used for the evaluation of the image quality in an Example. It is a figure for demonstrating the detail of the evaluation criteria of image quality in an Example.

In the present disclosure, the numerical range represented by using "-" means a range including the numerical values before and after "-" as the lower limit value and the upper limit value.
In the present disclosure, the amount of each component in the composition means the total amount of the plurality of substances present in the composition when a plurality of substances corresponding to each component are present in the composition, unless otherwise specified. do.
In the numerical range described stepwise in the present disclosure, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of another numerical range described stepwise. Further, it may be replaced with the value shown in the embodiment.
In the present disclosure, the term "process" is included in this term not only as an independent process but also as long as the intended purpose of the process is achieved even if it cannot be clearly distinguished from other processes.
In the present disclosure, the combination of preferred embodiments is a more preferred embodiment.

In the present disclosure, the pretreatment liquid for a non-permeable substrate means a pretreatment liquid applied to the impermeable substrate.
The pretreatment liquid for a non-permeable substrate can be applied to the impermeable substrate prior to the ink, for example, when recording an image with the ink on the impermeable substrate.
Further, the pretreatment liquid for a non-permeable substrate can also be used for producing a recording medium having a layer derived from the pretreatment liquid for a non-permeable substrate on the impermeable substrate. The obtained recording medium is used to apply ink on the layer of the recording medium to record an image.

In the present disclosure, the layer derived from the pretreatment liquid for a non-permeable substrate means a layer formed by applying the pretreatment liquid for a non-permeable substrate on a non-permeable substrate.
Hereinafter, the pretreatment liquid for a non-permeable substrate may be simply referred to as a “pretreatment liquid”. The layer derived from the pretreatment liquid for a non-permeable substrate may be simply referred to as "the layer derived from the pretreatment liquid".

[Pretreatment liquid for impermeable substrate]
The pretreatment liquid of the present disclosure (that is, the pretreatment liquid for a non-permeable substrate) contains water, three or more kinds of carboxylic acids, and a carboxylic acid content in which ClogP is less than -1.00. However, it is 2.0% by mass or less with respect to the total amount of the pretreatment liquid for a non-permeable substrate.

According to the pretreatment liquid of the present disclosure, it is possible to produce an image recording material or a recording medium in which the generation and blocking of precipitates are suppressed.
Specifically, the pretreatment liquid of the present disclosure is applied onto a non-permeable substrate to form a layer, and an ink containing a colorant and water is applied to a part of the formed layer to record an image. By doing so, it is possible to produce an image recording material in which the generation and blocking of precipitates are suppressed.
Further, by applying the pretreatment liquid of the present disclosure on a non-permeable substrate to form a layer, it is possible to produce a recording medium in which the generation and blocking of precipitates are suppressed.
The reason why the above effect is achieved is presumed as follows.

When an image recording material or a recording medium is produced using a pretreatment liquid containing water and a carboxylic acid, precipitates may be generated in the obtained image recording material or the recording medium. The precipitate is considered to be mainly a precipitate of carboxylic acid.
As a method for suppressing the generation of precipitates, a method using a highly hydrophilic (that is, low ClogP) carboxylic acid as the carboxylic acid in the pretreatment liquid can be considered.
However, by the study of the present inventors, it has been found that in the case of this method, blocking may occur in the obtained image recording material or the recorded medium. Here, blocking means that when an object to be contacted (for example, a non-permeable base material, an image recording object, a recording medium, etc.) is superposed on a surface to which a pretreatment liquid is applied in an image recording object or a recording medium. This means a phenomenon in which an object to be contacted adheres to the surface to which the pretreatment liquid is applied.
The pretreatment liquid of the present disclosure can suppress the generation of precipitates by containing three or more kinds of carboxylic acids. It is considered that the reason for this is that the inclusion of three or more kinds of carboxylic acids makes it difficult for the carboxylic acids to precipitate.
Further, the pretreatment liquid of the present disclosure does not contain a carboxylic acid having a ClogP of less than -1.00, or even if it contains a carboxylic acid, the content of the pretreatment liquid with respect to the total amount is limited to 2.0% by mass or less. By doing so, the occurrence of blocking can be suppressed.
According to the pretreatment liquid of the present disclosure, it is considered that the generation of precipitates and the generation of blocking can be suppressed as described above.

<Non-permeable substrate>
As described above, the pretreatment liquid for a non-permeable substrate of the present disclosure is a pretreatment liquid applied to a non-permeable substrate.

In the present disclosure, the non-permeable substrate refers to a substrate having a water absorption rate (unit: mass%, measurement time: 24 hours) of less than 0.2 in ASTM D570 (1988) of the ASTM test method.

The non-permeable base material is not particularly limited, but a resin base material is preferable.
The resin base material is not particularly limited, and examples thereof include a thermoplastic resin base material.
Examples of the resin base material include a base material obtained by molding a thermoplastic resin into a sheet or a film.
As the resin base material, a base material containing polypropylene, polyethylene terephthalate, nylon, polyethylene, or polyimide is preferable.

The resin base material may be a transparent resin base material or a colored resin base material.
Here, "transparency" means that the transmittance of visible light having a wavelength of 400 nm to 700 nm is 80% or more (preferably 90% or more).

The shape of the resin base material is not particularly limited, but is preferably a sheet-shaped resin base material, and more preferably a sheet-shaped resin base material capable of forming a roll by winding.
The thickness of the resin base material is preferably 10 μm to 200 μm, more preferably 10 μm to 100 μm.

The resin base material may be surface-treated from the viewpoint of improving the surface energy.
Examples of the surface treatment include, but are not limited to, corona treatment, plasma treatment, frame treatment, heat treatment, wear treatment, light irradiation treatment (UV treatment), flame treatment, and the like.

<Water>
The pretreatment liquid of the present disclosure contains water.
The content of water is preferably 50% by mass or more, more preferably 60% by mass or more, based on the total amount of the pretreatment liquid.
The upper limit of the water content depends on the amount of other components, but is preferably 90% by mass or less, more preferably 80% by mass or less, based on the total amount of the pretreatment liquid.

<Carboxylic acid>
The pretreatment liquid of the present disclosure contains three or more kinds of carboxylic acids.
The carboxylic acid has a function as a flocculant for agglomerating components (for example, colorants, resin particles, etc.) in the ink on a non-permeable substrate. By exerting such a function of the carboxylic acid, bleeding of the image recorded by applying ink on the pretreatment liquid is suppressed.
In the pretreatment liquid of the present disclosure, the generation of precipitates on the impermeable substrate is suppressed by containing three or more kinds of carboxylic acids.

Further, in the pretreatment liquid of the present disclosure, the content of the carboxylic acid having a ClogP of less than −1.00 is 2.0% by mass or less with respect to the total amount of the pretreatment liquid. This suppresses blocking, as described above.
From the viewpoint of further suppressing blocking, the content of the carboxylic acid having a ClogP of less than −1.00 with respect to the total amount of the pretreatment liquid is preferably 1.5% by mass or less, more preferably 1.0% by mass or less. It is more preferably 0.5% by mass or less. The lower limit of the content of the carboxylic acid whose ClogP is less than −1.00 with respect to the total amount of the pretreatment liquid is not particularly set, but is, for example, 0% by mass.

In the present disclosure, for ClogP of a carboxylic acid, a value calculated using ChemDraw® Professional (ver.16.0.1.4) (manufactured by PerkinElmer) is applied.
ClogP correlates with the degree of hydrophilicity, and the smaller the ClogP, the higher the hydrophilicity.

Each of the three or more carboxylic acids contained in the pretreatment liquid of the present disclosure may be a monocarboxylic acid (that is, a monovalent carboxylic acid) or a polyvalent carboxylic acid (that is, a divalent or higher carboxylic acid). Carboxylic acid).
Specific examples of the monocarboxylic acid and the polyvalent carboxylic acid will be described later.

The three or more types of carboxylic acids contained in the pretreatment liquid of the present disclosure preferably contain one or more polyvalent carboxylic acids, and include two or more polyvalent carboxylic acids, from the viewpoint of further suppressing image bleeding. It is more preferable, and it is further preferable to contain 3 or more kinds of polyvalent carboxylic acids.
Also, in general, the problem of precipitates is more likely to occur among carboxylic acids, especially multivalent carboxylic acids. However, in the pretreatment liquid of the present disclosure, the precipitation is suppressed even when the polyvalent carboxylic acid is contained by containing three or more kinds of carboxylic acids. That is, when three or more kinds of carboxylic acids contain one or more polyvalent carboxylic acids, the effect of suppressing precipitates by containing three or more kinds of carboxylic acids is more effectively exhibited.
The total amount of polyvalent carboxylic acid (that is, preferably 1 or more, more preferably 2 or more, still more preferably 3 or more) in the total amount of 3 or more carboxylic acids contained in the pretreatment liquid of the present disclosure. The proportion of the polyvalent carboxylic acid) is preferably 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and further preferably 80% by mass to 100% by mass.

The total content of the carboxylic acid contained in the pretreatment liquid is preferably 4.0% by mass to 15.0% by mass, more preferably 5.0% by mass to 13.% by mass, based on the total amount of the pretreatment liquid. It is 0% by mass, more preferably 5.0% by mass to 12.0% by mass, still more preferably 6.0% by mass to 10% by mass.
When the total content of the carboxylic acid is 4.0% by mass or more, the blurring of the image is further suppressed.
When the total content of the carboxylic acid is 15.0% by mass or less, the generation of precipitates and / or the generation of blocking is further suppressed.

The weight average ClogP of the carboxylic acid contained in the pretreatment liquid is preferably 0.50 or less, more preferably 0.30 or less, and further preferably 0. It is 10 or less, more preferably 0 or less.

The weight average ClogP of the carboxylic acid contained in the pretreatment liquid is preferably −1.00 or higher, more preferably −0.80 or higher, still more preferably −0. It is 60 or more, more preferably −0.50 or more.

In the present disclosure, the weight average ClogP means the weighted average value of ClogP of each carboxylic acid.
In the present disclosure, the weighted average value is X obtained by the following formula 1.

X = _ΣS _i Wi / ΣW _i ... (Formula 1)

The weight average ClogP of three or more kinds of carboxylic acids (that is, the ClogP of each carboxylic acid) is described in Equation 1 in S _i as the i-type (i represents an integer of 1 or more) contained in the pretreatment liquid. By substituting ClogP of the carboxylic acid and substituting the mass fraction of the carboxylic acid of the _i -type in the total carboxylic acid contained in the pretreatment liquid into Wi, it can be obtained as X in Equation 1.
For example, adipic acid (carboxylic acid with ClogP -0.02) 1% by mass, glutaric acid (carboxylic acid with ClogP -0.13) 5% by mass, and succinic acid (ClogP -0.53). In the pretreatment liquid containing 2% by mass of carboxylic acid), the weight average ClogP of these three carboxylic acids is determined to be −0.22 by the following formula.
X
= _ΣS _i Wi / ΣW _i
= [-0.02 x (1 / (1 + 5 + 2)) + (-0.13) x (5 / (1 + 5 + 2)) + (-0.53) x (2 / (1 + 5 + 2))]
= -0.22

From the viewpoint of further suppressing the generation of precipitates, the ratio of the total content of the carboxylic acid having a ClogP of 0.50 or less to the total amount of the three or more kinds of carboxylic acids contained in the pretreatment liquid is preferable. It is 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and further preferably 80% by mass to 100% by mass.
From the viewpoint of further suppressing the generation of precipitates, it is preferable that all of the three or more kinds of carboxylic acids contained in the pretreatment liquid are carboxylic acids having a ClogP of 0.50 or less.

From the viewpoint of further suppressing the occurrence of blocking, the ratio of the total content of the carboxylic acid having a ClogP of -1.00 or more to the total amount of the three or more carboxylic acids contained in the pretreatment liquid is preferable. It is 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and further preferably 80% by mass to 100% by mass.
From the viewpoint of further suppressing the generation of precipitates, it is preferable that all of the three or more kinds of carboxylic acids contained in the pretreatment liquid are carboxylic acids having a ClogP of −1.00 or more.

From the viewpoint of further suppressing the generation of precipitates and blocking, the total content of carboxylic acids having ClogP of -1.00 or more and 0.50 or less in the total amount of 3 or more kinds of carboxylic acids contained in the pretreatment liquid. The ratio of the amount is preferably 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and further preferably 80% by mass to 100% by mass.
From the viewpoint of further suppressing the generation of precipitates, it is preferable that all of the three or more kinds of carboxylic acids contained in the pretreatment liquid are carboxylic acids having a ClogP of −1.00 or more and 0.50 or less.

(Multivalent carboxylic acid)
As described above, the three or more kinds of carboxylic acids contained in the pretreatment liquid of the present disclosure preferably contain a polyvalent carboxylic acid.

The molecular weight of the polyvalent carboxylic acid is preferably 1000 or less, more preferably 500 or less, still more preferably 300 or less.
The lower limit of the molecular weight of the polyvalent carboxylic acid is, for example, 60, preferably 90 or more, and more preferably 100 or more.

Examples of the polyvalent carboxylic acid include compounds represented by the following general formula 1.

In the general formula 1, l is 1 or more, m is 0 or 1, n is 1 or more, and l + m + n is 2 or more. R ₁ to R ₄ independently represent a hydrogen atom, a hydroxyl group (OH), a carboxy group (COOH), an amino group (NH ₂ ), or an alkyl group having 1 to 4 carbon atoms.
Examples of the alkyl group having 1 to 4 carbon atoms in R ₁ to R ₄ include a methyl group, an ethyl group, a propyl group and a butyl group.

Independently, R ₁ to R ₄ are preferably a hydrogen atom or a carboxy group, and more preferably a hydrogen atom, from the viewpoint of ink cohesiveness.

L and n are preferably 1 to 3, and m is preferably 0.

In the general formula 1, l + m + n is preferably 3 to 8. When l + m + n is 3 or more, the polyvalent carboxylic acid can be made more hydrophobic and blocking is further suppressed. When l + m + n is 8 or less, the polyvalent carboxylic acid is suppressed from becoming too hydrophobic, and as a result, the generation of precipitates is further suppressed.
From the same viewpoint as above, l + m + n is more preferably 3 to 5.
Further, in the general formula 1, m is preferably 0, and when m is 0, l + n is preferably 3 to 5.

As the general formula 1, it is preferable that m is 0 and R ₁ to R ₄ are hydrogen atoms.
It is preferable that at least a part of the carboxy group in the general formula 1 is dissociated in the pretreatment liquid.

The weight average ClogP of the polyvalent carboxylic acid that can be contained in the pretreatment liquid of the present disclosure is preferably 0.50 or less, more preferably 0.30 or less, from the viewpoint of further suppressing the generation of precipitates. It is more preferably 0.10 or less, still more preferably 0 or less.

The weight average ClogP of the polyvalent carboxylic acid that can be contained in the pretreatment liquid of the present disclosure is preferably -1.00 or more, more preferably -0.80 or more, and further, from the viewpoint of further suppressing blocking. It is preferably −0.60 or higher, and more preferably −0.50 or higher.

From the viewpoint of further suppressing the generation of precipitates, the ratio of the total content of the polyvalent carboxylic acid having a ClogP of 0.50 or less to the total amount of the polyvalent carboxylic acid that can be contained in the pretreatment liquid is preferable. It is 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and further preferably 80% by mass to 100% by mass.
From the viewpoint of further suppressing the generation of precipitates, it is preferable that all of the polyvalent carboxylic acids that can be contained in the pretreatment liquid are polyvalent carboxylic acids having a ClogP of 0.50 or less.

From the viewpoint of further suppressing the occurrence of blocking, the ratio of the total content of the polyvalent carboxylic acid having a ClogP of -1.00 or more to the total amount of the polyvalent carboxylic acid that can be contained in the pretreatment liquid is preferable. It is 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and further preferably 80% by mass to 100% by mass.
From the viewpoint of further suppressing the generation of precipitates, it is preferable that all of the polyvalent carboxylic acids that can be contained in the pretreatment liquid are polyvalent carboxylic acids having a ClogP of −1.00 or higher.

From the viewpoint of further suppressing the generation of precipitates and blocking, the total content of polyvalent carboxylic acid having ClogP of -1.00 or more and 0.50 or less in the total amount of polyvalent carboxylic acid that can be contained in the pretreatment liquid. The ratio of the amount is preferably 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and further preferably 80% by mass to 100% by mass.
From the viewpoint of further suppressing the generation of precipitates, it is preferable that all of the polyvalent carboxylic acids that can be contained in the pretreatment liquid are polyvalent carboxylic acids having a ClogP of −1.00 or more and 0.50 or less.

The total content of the polyvalent carboxylic acid that can be contained in the pretreatment liquid is preferably 4.0% by mass to 15.0% by mass, more preferably 5.0% by mass or more, based on the total amount of the pretreatment liquid. It is 13.0% by mass, more preferably 5.0% by mass to 12.0% by mass, still more preferably 6.0% by mass to 10% by mass.
When the total content of the polyvalent carboxylic acid that can be contained in the pretreatment liquid is 4.0% by mass or more, blurring of the image is further suppressed.
When the total content of the polyvalent carboxylic acid that can be contained in the pretreatment liquid is 15.0% by mass or less, the generation of precipitates and / or the generation of blocking is further suppressed.

The three or more kinds of carboxylic acids contained in the pretreatment liquid of the present disclosure are from the viewpoint of further suppressing the generation of precipitates.
Polyvalent carboxylic acid A1, which is a polyvalent carboxylic acid having a ClogP of -1.00 or more and less than -0.50, and
Polyvalent carboxylic acid A2, which is a polyvalent carboxylic acid having a ClogP of -0.50 or more and -0.10 or less,
Polyvalent carboxylic acid A3, which is a polyvalent carboxylic acid having a ClogP of more than -0.10 and 0.50 or less,
Is preferably included.
In such a preferred embodiment, the polyvalent carboxylic acid A1, the polyvalent carboxylic acid A2, and the polyvalent carboxylic acid A3 may be only one kind or two or more kinds, respectively.

Hereinafter, specific examples of each of the polyvalent carboxylic acid A1, the polyvalent carboxylic acid A2, and the polyvalent carboxylic acid A3 will be shown, but each of the polyvalent carboxylic acid A1, the polyvalent carboxylic acid A2, and the polyvalent carboxylic acid A3 will be described. , Not limited to the following specific examples.

Examples of the polyvalent carboxylic acid A1 include succinic acid (ClogP = -0.53) and malonic acid (ClogP = -0.71).

Examples of the polyvalent carboxylic acid A2 include glutaric acid (ClogP = -0.13), maleic acid (ClogP = -0.17), itaconic acid (ClogP = -0.33), and fumaric acid (ClogP = -0). .17) and the like.

Examples of the polyvalent carboxylic acid A3 include adipic acid (ClogP = −0.02) and mesaconic acid (ClogP = 0.14).
As the three or more kinds of carboxylic acids contained in the pretreatment liquid, it is preferable to include at least one selected from the group consisting of adipic acid, glutaric acid, maleic acid, succinic acid or malonic acid, and preferably containing two or more kinds. More preferably, the three or more kinds of carboxylic acids contain only carboxylic acids selected from these groups.

The total mass of the polyvalent carboxylic acid A1 is [A1].
The total mass of the polyvalent carboxylic acid A2 is [A2].
When the total mass of the polyvalent carboxylic acid A3 is [A3],
The [A2] / ([A1] + [A3]) ratio is preferably 0.5 to 5.0, more preferably 0.5 to 4.0, and even more preferably 0.5 to 3. It is 0.
When the [A2] / ([A1] + [A3]) ratio is 0.5 to 5.0, the generation of precipitates is further suppressed.
In these preferred embodiments, it is not always necessary to include all of the polyvalent carboxylic acids A1 to A3. Even when one or two of the polyvalent carboxylic acids A1 to A3 are contained, if the [A2] / ([A1] + [A3]) ratio is within the above preferable range, the above preferred embodiment is used. Be included.

The total content of the polyvalent carboxylic acid A1, the polyvalent carboxylic acid A2, and the polyvalent carboxylic acid A3 (hereinafter, also referred to as "the total content of the polyvalent carboxylic acids A1 to A3") is based on the total amount of the pretreatment liquid. It is preferably 4.0% by mass to 15.0% by mass, more preferably 5.0% by mass to 13.0% by mass, and further preferably 5.0% by mass to 12.0% by mass. , More preferably 6.0% by mass to 10% by mass.
When the total content of the polyvalent carboxylic acids A1 to A3 is 4.0% by mass or more, the blurring of the image is further suppressed.
When the total content of the polyvalent carboxylic acids A1 to A3 is 15.0% by mass or less, the generation of precipitates is further suppressed.

The three or more kinds of carboxylic acids contained in the pretreatment liquid are polyvalent carboxylic acids other than polyvalent carboxylic acids A1 to A3 (that is, polyvalent carboxylic acids having ClogP of less than -1.00 or more than 0.50). Acid) may be contained.

Other polyvalent carboxylic acids include pimelic acid (ClogP = 0.51), propanthricarboxylic acid (ClogP = -1.08), malic acid (ClogP = -1.52), and citric acid (ClogP = -1. 75), citric acid (ClogP = -2.00), tartrate acid (ClogP = -3.22), polyacrylic acid, pimelic acid (ClogP = 1.44) and the like.

The ratio of the total content of the polyvalent carboxylic acids A1 to A3 to the total amount of the carboxylic acid contained in the pretreatment liquid is preferably 50% by mass to 100% by mass, and more preferably 60% by mass to 100%. It is by mass, more preferably 80% by mass to 100% by mass.

(Monocarboxylic acid)
The three or more kinds of carboxylic acids contained in the pretreatment liquid of the present disclosure may contain one or more kinds of monocarboxylic acids.
The monocarboxylic acid can also function as a flocculant that aggregates components in the ink (eg, colorants, resin particles, etc.).
Examples of the monocarboxylic acid include butyric acid (ClogP = 0.86), acetic acid (ClogP = -0.19), lactic acid (ClogP = -0.73), glycolic acid (ClogP = -1.04), and pyrrolidone carboxylic acid (ClogP = -1.04). ClogP = -1.15), comanoic acid (ClogP = -0.29), 2-furancarboxylic acid (ClogP = 1.06), 4-pyridinecarboxylic acid (ClogP = 0.78) and the like.

<Acids other than carboxylic acid>
The pretreatment liquid may contain at least one acid other than the carboxylic acid.
Acids other than carboxylic acids can also function as flocculants that aggregate components in the ink (eg, colorants, resin particles, etc.).
Examples of the acid other than the carboxylic acid include sulfonic acid (for example, benzenesulfonic acid), phosphoric acid, and the like.

The ratio of the carboxylic acid to the total amount of the acid contained in the pretreatment liquid is preferably 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and further preferably 80% by mass. ~ 100% by mass.

<Coagulant other than acid>
The pretreatment liquid of the present disclosure may contain at least one coagulant other than an acid as a coagulant that agglomerates components (for example, colorants, resin particles, etc.) in the ink.
Examples of the flocculant other than the acid include polyvalent metal salts, metal complexes, water-soluble cationic polymers and the like.
For coagulants other than acids, publicly known documents such as International Publication No. 2019/004485, International Publication No. 2019/150878, and International Publication No. 2019/163581 can be appropriately referred to.

When the pretreatment liquid of the present disclosure contains a flocculant other than the carboxylic acid, the content of the carboxylic acid in the entire flocculant is preferably 50% by mass to 100% by mass, more preferably 60% by mass or more. It is 100% by mass, more preferably 80% by mass to 100% by mass.

<Resin>
The pretreatment liquid of the present disclosure preferably contains at least one resin.
By containing the resin in the pretreatment liquid, the adhesion of the image to the impermeable substrate is ensured.
The resin that can be contained in the pretreatment liquid is not particularly limited, and examples thereof include known resins.

The glass transition temperature (Tg) of the resin that can be contained in the pretreatment liquid is preferably 0 ° C. to 120 ° C., more preferably 10 ° C. to 80 ° C., further preferably 15 ° C. to 60 ° C., and 20 ° C. to 60 ° C. More preferred.

In the present disclosure, the glass transition temperature of a resin means a value measured using differential scanning calorimetry (DSC).
The specific measurement of the glass transition temperature is carried out according to the method described in JIS K 7121 (1987) or JIS K 6240 (2011).
The glass transition temperature in the present disclosure is an extrapolated glass transition start temperature (hereinafter, may be referred to as Tig).
The method for measuring the glass transition temperature will be described more specifically.
When determining the glass transition temperature, hold it at a temperature about 50 ° C lower than the expected glass transition temperature of the resin particles until the device stabilizes, and then heat it at a heating rate of 20 ° C / min, which is higher than the temperature at which the glass transition is completed. Heat to a temperature about 30 ° C. higher to create a differential thermal analysis (DTA) curve or DSC curve.
The extra glass transition start temperature (Tig), that is, the glass transition temperature in the present disclosure, is a straight line extending the baseline on the low temperature side of the DTA curve or DSC curve to the high temperature side and the curve of the stepwise change portion of the glass transition. It is calculated as the temperature of the intersection with the tangent line drawn at the point where the gradient becomes maximum.

Further, in the present disclosure, when the pretreatment liquid contains two or more kinds of resins, the glass transition temperature of the resin contained in the pretreatment liquid is a weighted average of the glass transition temperatures of the resin contained in the pretreatment liquid. Means a value. Specifically, in the above-mentioned formula 1, Si is substituted with the glass transition temperature of the resin of the _i -type ( _i represents an integer of 1 or more) contained in the pretreatment liquid, and Wi is the pretreatment liquid. By substituting the mass fraction of the i-type resin particles (C) in the entire resin contained in the above, the weighted average value of the glass transition temperature of the resin contained in the pretreatment liquid is calculated as X in Equation 1. can do.

Examples of the resin that can be contained in the pretreatment liquid include urethane resin, polyester resin, acrylic resin, amide resin, urea resin, polycarbonate resin, olefin resin, styrene resin, polyalkylene glycol resin, polyvinyl alcohol resin, and the like.
The pretreatment liquid may contain only one type of resin, or may contain two or more types of resin.

Here, the acrylic resin is at least one selected from the group consisting of acrylic acid, a derivative of acrylic acid (for example, acrylic acid ester), methacrylic acid, and a derivative of methacrylic acid (for example, methacrylic acid ester). It means a polymer (homogeneous polymer or copolymer) of a raw material monomer containing.
That is, the concept of acrylic resin in the present disclosure includes not only a resin containing a structural unit derived from acrylic acid or a derivative thereof, but also a resin containing a structural unit derived from methacrylic acid or a derivative thereof.

The weight average molecular weight (Mw) of the resin that can be contained in the pretreatment liquid is preferably 1000 to 300,000, more preferably 2000 to 200,000, and even more preferably 5000 to 100,000.

In the present disclosure, weight average molecular weight (Mw) means a value measured by gel permeation chromatography (GPC) unless otherwise specified.
For the measurement by gel permeation chromatography (GPC), HLC (registered trademark) -8020GPC (Tosoh Corporation) was used as the measuring device, and TSKgel (registered trademark) Super Multipore HZ-H (4.6 mm ID ×) was used as the column. Use 3 bottles of 15 cm, Tosoh Corporation, and use THF (tetrahydrofuran) as the eluent. The measurement conditions are a sample concentration of 0.45% by mass, a flow velocity of 0.35 ml / min, a sample injection amount of 10 μl, and a measurement temperature of 40 ° C., using an RI detector.
The calibration curve is "Standard sample TSK standard, polystyrene": "F-40", "F-20", "F-4", "F-1", "A-5000", "A" of Tosoh Corporation. It is made from 8 samples of "-2500", "A-1000", and "n-propylbenzene".

The resin that can be contained in the pretreatment liquid may be a water-soluble resin or resin particles (that is, a water-insoluble resin).
In this disclosure
"Water insoluble" in a water-insoluble resin means the property that the amount dissolved in 100 g of water at 25 ° C. is less than 1.0 g (more preferably less than 0.5 g).
The "water-soluble" in the water-soluble resin means the property that the dissolution amount in 100 g of water at 25 ° C. is 1.0 g or more.

Specific examples of the water-soluble resin include polyalkylene glycol resins, polyvinyl alcohol resins, and the like.
Specific examples of the water-insoluble resin include urethane resin, polyester resin, acrylic resin, amide resin, urea resin, polycarbonate resin, olefin resin, styrene resin, and the like.

The resin that can be contained in the pretreatment liquid preferably contains resin particles from the viewpoint of further suppressing blocking and image bleeding.
In this case, the resin particles in the entire resin in the pretreatment liquid are preferably 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and further preferably 80% by mass to 100% by mass. %.

The volume average particle size of the resin particles is preferably 1 nm to 300 nm, more preferably 3 nm to 200 nm, and even more preferably 5 nm to 150 nm.

In the present disclosure, the volume average particle size means a value measured by a laser diffraction / scattering type particle size distribution meter.
Examples of the measuring device include a particle size distribution measuring device “Microtrack MT-3300II” (manufactured by Nikkiso Co., Ltd.).

The preferable resin particles that can be contained in the pretreatment liquid are at least one selected from the group consisting of acrylic resin particles, urethane resin particles, polyester resin particles, and composite particles containing an acrylic resin and a polyester resin.
For these preferable resin particles, publicly known documents such as International Publication No. 2019/150878 and International Publication No. 2019/163581 can be appropriately referred to.

When preparing the pretreatment liquid containing the resin particles, a commercially available product of the aqueous dispersion of the resin particles may be used.
Examples of commercially available products of the aqueous dispersion of acrylic resin particles include EM57DOC (manufactured by Daicel FineChem).
As the aqueous dispersion of the acrylic resin particles, the aqueous dispersion of the acrylic resin particles may be selected and used from the aqueous dispersion of the water-insoluble resin particles described in International Publication No. 2017/163738.
Commercially available products of the aqueous dispersion of polyester resin particles include, for example, Eastek1100, Eastek1200 (above, manufactured by Eastman Chemical Co., Ltd.), Pluscoat RZ570, Pluscoat Z687, Pluscoat Z565, Pluscoat RZ570, Pluscoat Z690 (above, GOO CHEMICAL CO., LTD.). (Manufactured by Chemical Industry Co., Ltd.), Byronal MD1200 (manufactured by Toyobo Co., Ltd.), and the like.
Examples of commercially available products of an aqueous dispersion of composite particles containing an acrylic resin and a polyester resin include pesresin A615GE and pesresin A613GE (all manufactured by Takamatsu Oil & Fat Co., Ltd.).
Examples of commercially available urethane resin particles include the "Superflex" series (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.).

The resin that can be contained in the pretreatment liquid is preferably an anionic resin from the viewpoint of further suppressing blocking and image bleeding.
The anionic resin means a resin containing an anionic group.
The anionic group is not particularly limited, but is preferably a carboxy group or a sulfo group, and more preferably a sulfo group.
The amount of the anionic group is not particularly limited, and is preferably 0.001 mol to 1.0 mol, more preferably 0.01 mol to 0.5 mol per 100 g of the resin.

When the pretreatment liquid contains a resin, the ratio of the content mass of the resin to the total content mass of three or more kinds of carboxylic acids (hereinafter, also referred to as "content mass ratio [resin / carboxylic acid]") is preferably 0. It is 3 to 3.5, more preferably 0.6 to 3.5, still more preferably 0.8 to 3.3, still more preferably 1.0 to 3.0.
When the content mass ratio [resin / carboxylic acid] is 0.3 or more, the adhesion of the layer derived from the pretreatment liquid to the impermeable substrate is further improved.
In general, when the content mass ratio [resin / carboxylic acid] is 0.3 or more, carboxylic acid precipitates tend to be easily formed. However, according to the pretreatment liquid of the present disclosure, By containing 3 or more kinds of carboxylic acids, the generation of carboxylic acid precipitates is suppressed even when the content mass ratio [resin / carboxylic acid] is 0.3 or more.
Further, when the content mass ratio [resin / carboxylic acid] is 3.5 or less, blurring of the image is further suppressed.

When the pretreatment liquid contains a resin, the content of the resin with respect to the total amount of the pretreatment liquid is preferably 1.0% by mass to 30.0% by mass, more preferably 2.0% by mass to 20.0. It is by mass, more preferably 3.0% by mass to 15.0% by mass, still more preferably 5.0% by mass to 15.0% by mass.

<Water-soluble solvent>
The pretreatment liquid of the present disclosure may contain at least one water-soluble solvent.

In the present disclosure, "water-soluble" in a water-soluble solvent means a property of dissolving 1 g or more in 100 g of water at 25 ° C.
The "water-soluble" property of the water-soluble solvent is preferably 3 g or more (more preferably 10 g or more) soluble in 100 g of water at 25 ° C.

As the water-soluble solvent, known ones can be used without particular limitation.
Examples of the water-soluble solvent include glycerin, 1,2,6-hexanetriol, trimethylolpropane, alcandiol (eg, ethylene glycol, propylene glycol (1,2-propanediol), 1,3-propanediol, 1 and 1). , 3-Butandiol, 1,4-Butanediol, 2-Buten-1,4-diol, 2-Ethyl-1,3-hexanediol, 2-Methyl-2,4-Pentinediol, 1,2-Octan Diol, 1,2-hexanediol, 1,2-pentanediol, 4-methyl-1,2-pentanediol, etc.), polyalkylene glycol (eg, diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, di Polyhydric alcohols such as propylene glycol, polyoxyethylene polyoxypropylene glycol, etc.;
Polyhydric alcohol ethers such as polyalkylene glycol ethers (eg, diethylene glycol monoalkyl ethers, triethylene glycol monoalkyl ethers, tripropylene glycol monoalkyl ethers, polyoxypropylene glyceryl ethers, etc.);
Alcohols having 1 to 4 carbon atoms, glycol ethers, 2-pyrrolidone, and N-methyl-2-pyrrolidone described in paragraph 0116 of JP-A-2011-42150;
And so on.
Of these, polyhydric alcohols or polyhydric alcohol ethers are preferable, and alkanediols, polyalkylene glycols, or polyalkylene glycol ethers are more preferable, from the viewpoint of suppressing the transcription of components.

(Surfactant)
The pretreatment liquid of the present disclosure may contain at least one of the surfactants.
The surfactant can be used as a surface tension modifier or an antifoaming agent. Examples of the surface tension adjusting agent or defoaming agent include nonionic surfactants, cationic surfactants, anionic surfactants, betaine surfactants and the like. Of these, a nonionic surfactant or an anionic surfactant is preferable from the viewpoint of the aggregation rate of the ink.

Preferred surfactants include acetylene glycol-based surfactants, which are a type of nonionic surfactants.
As the acetylene glycol-based surfactant, for example, the acetylene glycol-based surfactant described in paragraphs 0070 to 0080 of International Publication No. 2017/149917 can be used.
As an example of an acetylene glycol-based surfactant,
2,4,7,9-Tetramethyl-5-decyne-4,7-diol polyalkylene oxide adduct (preferably polyethylene oxide adduct),
Polyalkylene oxide adduct of 3,6-dimethyl-4-octyne-3,6-diol (preferably polyethylene oxide adduct),
A polyalkylene oxide adduct of 2,5,8,11-tetramethyl-6-dodecine-5,8-diol (preferably a polyethylene oxide adduct),
Polyalkylene oxide adduct of 2,5-dimethyl-3-hexyne-2,5-diol (preferably polyethylene oxide adduct)
And so on.
Commercially available products of acetylene glycol-based surfactants include the Surfinol series manufactured by Air Products and Chemicals, Inc. (for example, Surfinol 420, Surfinol 440, Surfinol 465, Surfinol 485), orol. Examples include fin series (for example, Orfin E1010, Orfin E1020), Dynol series (for example, Dynol 604); acetylenol manufactured by Kawaken Fine Chemicals Co., Ltd .; and the like.
Commercially available products of acetylene glycol-based surfactants are also provided by Dow Chemical Co., Ltd., General Aniline Co., Ltd. and the like.

Examples of the surfactant include pages 37 to 38 of JP-A-59-157636 and Research Disclosure No. Also included are compounds listed as surfactants in 308119 (1989). Further, the fluorine (alkyl fluoride-based) surfactants, silicone-based surfactants and the like described in JP-A-2003-322926, JP-A-2004-325707, and JP-A-2004-309806 are also mentioned. ..

When the pretreatment liquid of the present disclosure contains a surfactant, the content of the surfactant in the pretreatment liquid is not particularly limited, but the content is such that the surface tension of the pretreatment liquid is 50 mN / m or less. The content is preferably 20 mN / m to 50 mN / m, more preferably 30 mN / m to 45 mN / m, and even more preferably 30 mN / m to 45 mN / m.
For example, when the pretreatment liquid contains a surfactant as a defoaming agent, the content of the surfactant as a defoaming agent is preferably 0.0001% by mass to 1% by mass with respect to the total amount of the pretreatment liquid. , 0.001% by mass to 0.1% by mass is more preferable.

(Other ingredients)
The pretreatment liquid of the present disclosure may contain other components other than the above, if necessary.
Other components that may be contained in the pretreatment solution include solid wetting agents, colloidal silica, inorganic salts, anti-fading agents, emulsion stabilizers, penetration promoters, UV absorbers, preservatives, fungicides, pH regulators, etc. Water-soluble polymer compounds other than viscosity regulators, rust preventives, chelating agents, and water-soluble cationic polymers (for example, water-soluble polymer compounds described in paragraphs 0026 to 0080 of JP2013-001854), etc. Known additives are mentioned.

(Physical characteristics of pretreatment liquid)
The pH of the pretreatment liquid of the present disclosure at 25 ° C. is preferably 0.5 to 6.0.
When the pH of the pretreatment liquid at 25 ° C. is 0.5 or more, the roughness of the impermeable substrate is further reduced, and the adhesion of the image portion is further improved.
When the pH of the pretreatment solution at 25 ° C. is 6.0 or less, the aggregation rate is further improved, the coalescence of dots (ink dots) due to ink on the impermeable substrate is further suppressed, and the image is grainy. Is further reduced.
The pH of the pretreatment liquid at 25 ° C. is more preferably 0.5 to 5.0.
The pH in the present disclosure means a value measured using a pH meter.

The viscosity of the pretreatment liquid of the present disclosure is preferably in the range of 0.5 mPa · s to 10 mPa · s, more preferably in the range of 1 mPa · s to 5 mPa · s, from the viewpoint of the aggregation rate of the ink.

The viscosity in the present disclosure is a value measured at 25 ° C. using a viscometer.
As the viscometer, for example, a VISCOMETER TV-22 type viscometer (manufactured by Toki Sangyo Co., Ltd.) can be used.

The surface tension of the pretreatment liquid of the present disclosure is preferably 60 mN / m or less, more preferably 20 mN / m to 50 mN / m, and even more preferably 30 mN / m to 45 mN / m.
When the surface tension of the pretreatment liquid is within the above range, the adhesion between the impermeable substrate and the pretreatment liquid is improved.

The surface tension in the present disclosure is a value measured at a temperature of 25 ° C.
The surface tension can be measured by using, for example, Automatic Surface Tensiometer CBVP-Z (manufactured by Kyowa Surface Science Co., Ltd.).

[Ink set]
The ink set of the present disclosure includes the above-mentioned pretreatment liquid of the present disclosure and an ink containing a colorant and water.
In the ink set of the present disclosure, the pretreatment liquid of the present disclosure is applied onto a non-permeable substrate, and ink is applied to a part of the region to which the pretreatment liquid is applied on the impermeable substrate. It is suitably used for image recording in an aspect of recording an image (for example, the image recording method of the present disclosure described later).
Since the ink set of the present disclosure includes the above-mentioned pretreatment liquid of the present disclosure, the ink set of the present disclosure has the same effect as that of the above-mentioned pretreatment liquid of the present disclosure. That is, according to the ink set of the present disclosure, it is possible to produce an image recording material in which the generation and blocking of precipitates are suppressed.

<Pretreatment liquid>
The ink set of the present disclosure comprises the pretreatment liquid of the present disclosure described above.
The ink set of the present disclosure may be provided with only one type of the above-mentioned pretreatment liquid of the present disclosure, or may be provided with two or more types.

<Ink>
The ink set of the present disclosure comprises an ink containing a colorant and water.
The ink set of the present disclosure may include only one type of the above ink, or may include two or more types of the ink.
In the ink set of the present disclosure, according to the embodiment including two or more kinds of the above inks, a multicolor image can be recorded.
For two or more types of ink,
Three types of ink consisting of cyan ink, magenta ink, and yellow ink;
Four types of ink consisting of cyan ink, magenta ink, yellow ink, and black ink;
Four or more kinds of inks consisting of the above three kinds of colored inks and at least one selected from white ink, green ink, orange ink, violet ink, light cyan ink, light magenta ink and light yellow ink;
Five or more types of inks consisting of the above four types of colored inks, at least one selected from white ink, green ink, orange ink, violet ink, light cyan ink, light magenta ink, and light yellow ink;
And so on.
However, two or more kinds of inks are not limited to these specific examples.

As the ink, inkjet ink is preferable from the viewpoint of the image quality of the recorded image and the like.

Hereinafter, each component that can be contained in the ink will be described.

(Colorant)
The ink contains at least one colorant.
The colorant is not particularly limited, and known colorants can be used, but organic pigments or inorganic pigments are preferable.

Examples of the organic pigment include azo pigments, polycyclic pigments, dye chelate, nitro pigments, nitroso pigments, aniline black, and the like. Among these, azo pigments, polycyclic pigments and the like are more preferable.
Examples of the inorganic pigment include titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, chrome yellow, carbon black, and the like. Of these, carbon black is particularly preferred.
As the colorant, the colorant described in paragraphs 0996 to 0100 of JP-A-2009-241586 is preferably mentioned.

The content of the colorant is preferably 1% by mass to 25% by mass, more preferably 2% by mass to 20% by mass, and particularly preferably 2% by mass to 15% by mass with respect to the total amount of the ink.

(Dispersant)
The ink may contain a dispersant for dispersing the colorant. The dispersant may be either a polymer dispersant or a small molecule surfactant-type dispersant. Further, the polymer dispersant may be either a water-soluble dispersant or a water-insoluble dispersant.
As the dispersant, for example, the dispersant described in paragraphs 0080 to 0906 of JP-A-2016-145312 is preferably mentioned.

The mixed mass ratio (p: s) of the colorant (p) and the dispersant (s) is preferably in the range of 1: 0.06 to 1: 3, and preferably in the range of 1: 0.125 to 1: 2. It is more preferably 1: 0.125 to 1: 1.5.

(water)
The ink contains water.
The water content is preferably 50% by mass or more, more preferably 60% by mass or more, based on the total amount of the ink.
The upper limit of the water content depends on the amount of other components, but is preferably 90% by mass or less, more preferably 80% by mass or less, based on the total amount of the ink.

(Resin particles)
The ink preferably contains resin particles.
This further improves the adhesion and image quality of the image.

As the resin particles, at least one of acrylic resin particles and urethane resin particles is preferable from the viewpoint of further improving the adhesion and image quality of the image.
The meanings of the acrylic resin particles and the urethane resin particles that can be contained in the ink are the same as the meanings of the acrylic resin particles and the urethane resin particles that can be contained in the pretreatment liquid described above.

The resin particles that can be contained in the ink preferably contain acrylic resin particles from the viewpoint of further improving the adhesion of the image.

As the acrylic resin particles, acrylic resin particles which are self-dispersing resin particles are also preferable.
Examples of the self-dispersible resin particles include the self-dispersible polymer particles described in paragraphs 0062 to 0076 of JP-A-2016-188345.

When the resin particles that can be contained in the ink contain acrylic resin particles, the ratio of the acrylic resin particles to the resin particles that can be contained in the ink is preferably 60% by mass or more, more preferably 80% by mass or more. More preferably, it is 90% by mass or more.
When the ratio of the acrylic resin particles to the resin particles that can be contained in the ink is 60% by mass or more, the adhesion of the image is further improved.

The glass transition temperature of the resin particles that can be contained in the ink is not particularly limited, but is preferably 150 ° C. or lower, more preferably 130 ° C. or lower, from the viewpoint of manufacturing aptitude of the resin particles.
The lower limit of the glass transition temperature of the resin particles that can be contained in the ink is not particularly limited, but is, for example, 50 ° C, preferably 80 ° C.
The method for measuring the glass transition temperature is as described above.

Further, the resin in the resin particles that can be contained in the ink is preferably a water-insoluble resin.

The volume average particle size ( _Pi ) of the resin particles that can be contained in the ink is preferably 1 nm to 200 nm, more preferably 3 nm to 200 nm, and further preferably 5 nm to 50 nm.
The method for measuring the volume average particle size of the resin particles is as described above.

The weight average molecular weight (Mw) of each resin in the resin particles that can be contained in the ink is preferably 1000 to 300,000, more preferably 2000 to 200,000, still more preferably 5000 to 100,000, respectively. ..
The method for measuring Mw is as described above.

The resin in the resin particles that can be contained in the ink preferably has an alicyclic structure or an aromatic ring structure, and more preferably has an aromatic ring structure.
As the alicyclic structure, an alicyclic hydrocarbon structure having 5 to 10 carbon atoms is preferable, and a cyclohexane ring structure, a dicyclopentanyl ring structure, a dicyclopentenyl ring structure, or an adamantane ring structure is preferable.
As the aromatic ring structure, a naphthalene ring or a benzene ring is preferable, and a benzene ring is more preferable.
The amount of the alicyclic structure or the aromatic ring structure is not particularly limited, and is preferably 0.01 mol to 1.5 mol, more preferably 0.1 mol to 1 mol, for example, per 100 g of the resin.

The resin in the resin particles that can be contained in the ink is preferably an anionic resin (that is, a resin containing an anionic group).
The anionic group is not particularly limited, but is preferably a carboxy group or a sulfo group, and more preferably a carboxy group.
The amount of the anionic group is not particularly limited, and is preferably 0.001 mol to 1.0 mol, more preferably 0.01 mol to 0.5 mol per 100 g of the resin.

The content of the resin particles with respect to the total amount of the ink is preferably 1% by mass to 25% by mass, more preferably 2% by mass to 20% by mass, and further preferably 3% by mass to 15% by mass. preferable.

(Water-soluble solvent)
The ink preferably contains at least one of the water-soluble solvents.
Thereby, the effect of suppressing the drying of the ink or the effect of wetting the ink can be obtained.
The water-soluble solvent that can be contained in the ink can be used, for example, as a drying inhibitor that prevents the ink from adhering and drying at the ink ejection port of the injection nozzle to form aggregates and clogging.
From the viewpoint of suppressing drying and wetting, the water-soluble solvent contained in the ink is preferably a water-soluble solvent having a lower vapor pressure than water.
The boiling point of the water-soluble solvent at 1 atm (1013.25 hPa) is preferably 80 ° C to 300 ° C, more preferably 120 ° C to 250 ° C.

The anti-drying agent is preferably a water-soluble solvent having a lower vapor pressure than water.
Specific examples of such a water-soluble solvent include ethylene glycol, propylene glycol, diethylene glycol, polyethylene glycol, thiodiglycol, dithiodiglycol, 2-methyl-1,3-propanediol, 1,2,6-hexanetriol. , Polyhydric alcohols typified by acetylene glycol derivatives, glycerin, trimethylolpropane and the like.
Of these, as the anti-drying agent, polyhydric alcohols such as glycerin and diethylene glycol are preferable.
The anti-drying agent may be used alone or in combination of two or more. The content of the anti-drying agent is preferably in the range of 10% by mass to 50% by mass with respect to the total amount of the ink.

In addition to the above, the water-soluble solvent may be used for adjusting the viscosity of the ink.
Specific examples of the water-soluble solvent that can be used for adjusting the viscosity include alcohols (eg, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, t-butanol, pentanol, hexanol, cyclohexanol, (Benzyl alcohol), polyhydric alcohols (eg ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentandiol, glycerin, hexanetriol, thiodiglycol) ), Glycol derivatives (eg, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, triethylene glycol). Monomethyl ether, ethylene glycol diacetate, ethylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, ethylene glycol monophenyl ether), amines (eg, ethanolamine, diethanolamine, triethanolamine, N-methyl) Diethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, diethylenetriamine, triethylenetetramine, polyethyleneimine, tetramethylpropylenediamine), and other polar solvents (eg, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, sulfolane, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone, acetonitrile, acetone) Is included.
In this case, the water-soluble solvent may be used alone or in combination of two or more.

(Other additives)
The ink may contain other components other than the above components.
Other components include, for example, anti-fading agents, emulsion stabilizers, penetration promoters, UV absorbers, preservatives, fungicides, pH regulators, surface tension regulators, defoamers, viscosity regulators, dispersion stability. Known additives such as agents, rust preventives, chelating agents and the like can be mentioned.

(Preferable physical characteristics of ink)
The viscosity of the ink is preferably 1.2 mPa · s or more and 15.0 mPa · s or less, more preferably 2 mPa · s or more and less than 13 mPa · s, and 2.5 mPa · s or more and less than 10 mPa · s. Is preferable.
The method for measuring the viscosity is as described above.

The surface tension of the ink is preferably 25 mN / m or more and 40 mN / m or less, and more preferably 27 mN / m or more and 37 mN / m or less.
The method for measuring the surface tension is as described above.

The pH of the ink of the present disclosure at 25 ° C. is preferably pH 6 to 11, more preferably pH 7 to 10, and even more preferably pH 7 to 9 from the viewpoint of dispersion stability.
The method for measuring pH is as described above.

[Image recording method]
The image recording method of the present disclosure is
A step of applying the pretreatment liquid of the present disclosure on a non-permeable substrate to form a layer (that is, a layer derived from the pretreatment liquid).
A step of applying an ink containing a colorant and water to a part of the above layer (that is, a layer derived from the pretreatment liquid) and recording an image.
Have.
The image recording method of the present disclosure may include other steps, if necessary.

In the image recording method of the present disclosure, the pretreatment liquid of the present disclosure is used.
Therefore, according to the image recording method of the present disclosure, the same effect as that of the pretreatment liquid of the present disclosure is obtained (that is, the generation of precipitates and the generation of blocking are suppressed).

<Step of applying pretreatment liquid>
The step of applying the pretreatment liquid is a step of applying the pretreatment liquid on the surface of the impermeable substrate to form a layer.

The pretreatment liquid can be applied to the impermeable substrate by applying a known method such as a coating method, an inkjet method, or a dipping method.
As a coating method, a bar coater (for example, a wire bar coater), an extrusion die coater, an air doctor coater, a blade coater, a rod coater, a knife coater, a squeeze coater, a reverse roll coater, a gravure coater, a flexo coater and the like are known. The coating method can be mentioned.
The details of the inkjet method are the same as those of the inkjet method that can be applied to the step of applying ink, which will be described later.

The applied mass (g / m ² ) of the pretreatment liquid per unit area is not particularly limited as long as the components in the ink can be aggregated, but is preferably 0.1 g / m ² to 10 g / m ² . It is preferably 0.5 g / m ² to 6.0 g / m ² , and more preferably 1.0 g / m ² to 4.0 g / m ² .

Further, in the step of applying the pretreatment liquid, the impermeable substrate may be heated before the application of the pretreatment liquid.
The heating temperature may be appropriately set according to the type of the impermeable substrate or the composition of the pretreatment liquid, but the temperature of the impermeable substrate is preferably 20 ° C to 50 ° C, preferably 25 ° C to 50 ° C. More preferably, it is 40 ° C.

In the step of applying the pretreatment liquid, the pretreatment liquid may be heated and dried to form a layer after the application of the pretreatment liquid and before the step of applying the ink described later.
Examples of the means for heating and drying the pretreatment liquid include known heating means such as a heater, known blowing means such as a dryer, and means combining these.
As a method for heating and drying the pretreatment liquid, for example,
A method of applying heat with a heater or the like from the side opposite to the surface to which the pretreatment liquid of the impermeable substrate is applied.
A method of applying warm air or hot air to the surface of the impermeable substrate to which the pretreatment liquid has been applied.
A method of applying heat with an infrared heater from the side of the impermeable substrate to which the pretreatment liquid is applied or the surface to which the pretreatment liquid is applied.
A method that combines multiple of these,
And so on.

The heating temperature during heat drying is preferably 35 ° C. or higher, more preferably 40 ° C. or higher.
The upper limit of the heating temperature is not particularly limited, but examples of the upper limit include 100 ° C, preferably 90 ° C, and more preferably 70 ° C.
The time for heating and drying is not particularly limited, but is preferably 0.5 seconds to 60 seconds, more preferably 0.5 seconds to 20 seconds, and particularly preferably 0.5 seconds to 10 seconds.

<Process of recording images>
The step of recording an image is a step of applying an ink containing a colorant and water to a part of the above layer (that is, a layer derived from the pretreatment liquid) to record an image.
By this step, ink can be selectively applied onto the impermeable substrate, whereby a desired image (specifically, a visible image) can be recorded.

In the step of applying ink, only one type of ink may be applied to a part of the layer derived from the pretreatment liquid, or two or more types of ink may be applied. In the process of applying ink, when two or more colors of ink are applied, an image of two or more colors can be recorded.

As a method of applying ink in the step of applying ink, known methods such as a coating method, an inkjet method, and a dipping method can be applied.
Above all, the inkjet method is preferable.
The ink ejection method in the inkjet method is not particularly limited, and is known, for example, a charge control method for ejecting ink using electrostatic attraction, and a drop-on-demand method (pressure) using the vibration pressure of a piezo element. (Pulse method), an acoustic inkjet method that converts an electric signal into an acoustic beam and irradiates the ink to eject the ink using radiation pressure, and a thermal inkjet method that heats the ink to form bubbles and uses the generated pressure. It may be any of the bubble jet (registered trademark) method and the like.
As the inkjet method, in particular, by the method described in JP-A-54-59936, the ink subjected to the action of heat energy causes a rapid volume change, and the ink is ejected from the nozzle by the acting force due to this state change. It is possible to effectively use the inkjet method for making the ink jet.
As the inkjet method, the method described in paragraphs 093 to 0105 of JP-A-2003-306623 can also be applied.

The ink is applied to the region to which the pretreatment liquid of the impermeable substrate is applied by the inkjet method by ejecting the ink from the nozzle of the inkjet head.
As the inkjet head method, a shuttle method that records while scanning a short serial head in the width direction of the impermeable base material and a recording element that corresponds to the entire area of one side of the impermeable base material are arranged. There is a line method using a line head that has been used.
In the line method, image recording can be performed on the entire surface of the impermeable substrate by scanning the impermeable substrate in a direction intersecting the arrangement direction of the recording elements. The line system eliminates the need for a transport system such as a carriage that scans a short head in the shuttle system. Further, in the line method, as compared with the shuttle method, the movement of the carriage and the complicated scanning control with the impermeable base material become unnecessary, and only the impermeable base material moves. Therefore, according to the line method, the speed of image recording is realized as compared with the shuttle method.

The amount of ink droplets ejected from the nozzle of the inkjet head is preferably 1 pL (picolitre) to 10 pL, more preferably 1.5 pL to 6 pL, from the viewpoint of obtaining a high-definition image.
Further, from the viewpoint of improving the unevenness of the image and the connection of continuous gradation, it is also effective to eject a combination of different droplet amounts.

In the step of applying the ink, the applied ink may be heated and dried.
Examples of the means for performing heat drying include known heating means such as a heater, known blowing means such as a dryer, and means combining these.
As a method for heating and drying the ink, for example,
A method of applying heat with a heater or the like from the side opposite to the surface to which the ink of the impermeable substrate is applied.
A method of applying warm air or hot air to the ink-applied surface of a non-permeable substrate,
A method of applying heat with an infrared heater from the side opposite to the surface to which the ink of the impermeable substrate is applied or the surface to which the pretreatment liquid is applied.
A method that combines multiple of these,
And so on.

The heating temperature during heat drying is preferably 55 ° C. or higher, more preferably 60 ° C. or higher, and particularly preferably 65 ° C. or higher.
The upper limit of the heating temperature is not particularly limited, but examples of the upper limit include 100 ° C., preferably 90 ° C.
The time for heating and drying the ink is not particularly limited, but is preferably 3 seconds to 60 seconds, more preferably 5 seconds to 60 seconds, and particularly preferably 10 seconds to 45 seconds.

Further, in the step of applying the ink, the impermeable base material (specifically, the impermeable base material to which the pretreatment liquid is applied in the step of applying the pretreatment liquid) is heated before applying the ink. You may.
The heating temperature may be appropriately set according to the type of the impermeable substrate and / or the composition of the ink, but the temperature of the impermeable substrate is preferably 20 ° C to 50 ° C, preferably 25 ° C to 50 ° C. More preferably, it is 40 ° C.
In the step of applying the pretreatment liquid, when the pretreatment liquid is heated and dried, even if the heating for heating and drying the pretreatment liquid also heats the impermeable base material before applying the ink. good.

The image recording method of the present disclosure may include other steps, if necessary.
As other steps, a step of forming an overcoat layer covering the region to which the pretreatment liquid is applied and a part of the region where the pretreatment liquid is applied, and an image of the impermeable substrate on which the image is recorded are provided. A step of laminating a laminating base material on the side of the surface, and the like can be mentioned.

[Example of image recording device]
Hereinafter, an example of an image recording apparatus that can be suitably used for the image recording method of the present disclosure will be described with reference to FIG.

FIG. 1 is a diagram conceptually showing an example of an image recording device.
As shown in FIG. 1, in the image recording apparatus according to this example, a long non-permeable base material S1 wound in a roll shape is unwound by an unwinding device W1 and unwound. The permeable base material S1 is conveyed in the direction of the block arrow, passed through the pretreatment liquid application device A1, the pretreatment liquid drying zone Dry1, the inkjet ink application device IJ1, and the ink drying zone Dry2 in this order, and finally the winding device. It is a device to wind up with W2.
Since FIG. 1 is a conceptual diagram, the transport path of the impermeable base material S1 is simplified, and the impermeable base material S1 is shown as if it is transported in one direction. In practice, it goes without saying that the transport path of the impermeable substrate S1 may be meandering. As a transport method for the impermeable substrate S1, various web transport methods such as a body and a roller can be appropriately selected.

In the pretreatment liquid application device A1 and the pretreatment liquid drying zone Dry1, the step of applying the pretreatment liquid in the image recording method according to the above-mentioned example is carried out. The pretreatment liquid drying zone Dry1 may be omitted.
As the method and conditions for applying the pretreatment liquid in the pretreatment liquid application device A1, the methods and conditions exemplified in the section “Image recording method” can be applied.
As for the drying method and conditions in the pretreatment liquid drying zone Dry1, the methods and conditions exemplified in the description of the section “Image recording method” can be applied.
Further, on the upstream side of the impermeable base material S1 in the transport direction with respect to the pretreatment liquid applying device A1, a surface treatment portion (preferably corona treatment) for applying a surface treatment (preferably corona treatment) to the impermeable base material S1 (not shown). ) May be provided.

The above-mentioned step of applying ink is carried out by the ink applying device IJ1 and the ink drying zone Dry2. The ink drying zone Dry2 may be omitted.
As for the method and conditions for applying ink in the ink applying device IJ1, the methods and conditions exemplified in the section of the step of applying ink can be applied.
As for the drying method and conditions in the ink drying zone Dry2, the methods and conditions exemplified in the section of the step of applying ink can be applied.

Although not shown, the structure of the ink applying device IJ1 can be a structure including at least one inkjet head.
The inkjet head may be a shuttle head, but from the viewpoint of speeding up image recording, a line head in which a large number of ejection ports (nozzles) are arranged in the width direction of a long non-permeable substrate is preferable.
From the viewpoint of speeding up image recording, the structure of the ink applying device IJ1 is preferably a line head for black (K) ink, a line head for cyan (C) ink, and a line head for magenta (M) ink. And at least one of the line heads for yellow (Y) ink.
The structure of the ink applying device IJ1 is more preferably provided with at least two of the above four line heads, and these two or more line heads are provided in the transport direction of the impermeable substrate (direction of the block arrow). It is an arrayed structure.
The ink application device IJ1 further includes a line head for white ink, a line head for orange ink, a line head for green ink, a line head for purple ink, a line head for light cyan ink, and a line for light magenta ink. At least one of the heads may be provided with a line head.

As described above, in the image recording apparatus according to this example, the long non-penetrating base material S1 wound in a roll shape is unwound by the unwinding device W1 and unwound the impermeable base material. S1 is conveyed in the direction of the block arrow, the pretreatment liquid is applied and dried by the pretreatment liquid application device A1 and the pretreatment liquid drying zone Dry1, and then the ink is applied by the inkjet ink application device IJ1 and the ink drying zone Dry2. And by drying, the image can be recorded. The impermeable substrate S1 (that is, the image recording material) on which the image is recorded is taken up by the unwinding device W2.

[Image recording]
The image recordings of this disclosure are
With a non-permeable substrate,
A layer (a layer that is a dry product of the pretreatment liquid) arranged on a non-permeable substrate and formed by the pretreatment liquid of the present disclosure, and
An image containing a colorant placed partly on this layer,
To prepare for.

Since the image recording material of the present disclosure includes a layer formed by the pretreatment liquid of the present disclosure (a layer which is a dried product of the pretreatment liquid), the same effect as that of the pretreatment liquid of the present disclosure is exhibited (that is,). , The generation of precipitates and the generation of blocking are suppressed).

The image recording material of the present disclosure is suitably produced by the above-mentioned image recording method of the present disclosure.
Specifically, the layer arranged on the impermeable substrate is formed by applying the pretreatment liquid of the present disclosure on the impermeable substrate.
In the image recording material, the interface between the image (that is, the image derived from the ink) and the layer (that is, the layer derived from the pretreatment liquid) does not necessarily have to be clear. For example, there may be a region between the image and the layer in which the ink component, the pretreatment liquid component, and the ink component are mixed.

The image recording may include layers and other elements other than the image, if necessary.
Other elements include an overcoat layer arranged to cover the layer and the image, a laminated substrate laminated to cover the layer and the image, and the like.

[Manufacturing method of recorded medium]
The method for producing a recording medium of the present disclosure includes a step of applying the pretreatment liquid of the present disclosure on a non-permeable substrate to form a layer.
The method for producing a recording medium of the present disclosure may include other steps, if necessary.

In the method for producing a recording medium of the present disclosure, the pretreatment liquid of the present disclosure is used.
Therefore, according to the method for producing a recording medium of the present disclosure, the same effect as that of the pretreatment liquid of the present disclosure is obtained (that is, the generation of precipitates and the generation of blocking are suppressed).

The preferred embodiment of the step of applying the pretreatment liquid in the method for producing a recording medium of the present disclosure is the same as the preferred embodiment of the step of applying the pretreatment liquid in the image recording method of the present disclosure.
A preferred embodiment of the method for manufacturing a recording medium of the present disclosure is an aspect of omitting the step of recording an image from the image recording method of the present disclosure (for example, before the step of recording an image in the image recording method of the present disclosure). Aspect).

The method for manufacturing the recorded medium of the present disclosure can be carried out, for example, by using the image recording apparatus (see FIG. 1) according to the above-mentioned example.
In this case, for example, the long non-permeable base material S1 wound in a roll shape is unwound by the unwinding device W1, and the unwound non-permeable base material S1 is conveyed in the direction of the block arrow. Then, the pretreatment liquid is applied and dried by the pretreatment liquid application device A1 and the pretreatment liquid drying zone Dry1, and then the ink is not applied and dried by the inkjet ink application device IJ1 and the ink drying zone Dry2, and the pretreatment is performed. The impermeable base material S1 (that is, the recording medium) to which the liquid has been applied and dried is taken up by the unwinding device W2.

Further, the method for manufacturing a recorded medium of the present disclosure has a structure in which the inkjet ink applying device IJ1 and the ink drying zone Dry2 in the structure of the image recording device (see FIG. 1) according to the above-mentioned example are omitted. It can also be carried out using a device.

[Recorded medium]
The recording medium of the present disclosure is
With a non-permeable substrate,
A layer (a layer that is a dry product of the pretreatment liquid) arranged on a non-permeable substrate and formed by the pretreatment liquid of the present disclosure, and
To prepare for.

Since the image recording material of the present disclosure includes a layer formed by the pretreatment liquid of the present disclosure (a layer which is a dried product of the pretreatment liquid), the same effect as that of the pretreatment liquid of the present disclosure is exhibited (that is,). , The generation of precipitates and the generation of blocking are suppressed).
The recorded medium of the present disclosure is suitably manufactured by the above-mentioned manufacturing method of the recorded medium of the present disclosure.

The preferred embodiment of the layer in the recorded medium of the present disclosure is the same as the preferred embodiment of the layer in the image recording material of the present disclosure.
A preferred embodiment of the recorded medium of the present disclosure is an embodiment in which an image is omitted from the image recording material of the present disclosure.
The image recording material of the present disclosure can be manufactured by applying the above-mentioned ink to a part of the layer of the recording medium of the present disclosure and recording an image.

Hereinafter, examples of the present disclosure will be shown, but the present disclosure is not limited to the following examples.
In the following, unless otherwise specified, "parts" and "%" are based on mass.
Further, in the following, "water" means ion-exchanged water unless otherwise specified.

[Example 1]
<Preparation of pretreatment liquid>
A pretreatment solution having the following composition was prepared.

-Composition of pretreatment liquid-
・ Adipic acid (multivalent carboxylic acid)
… 1.0% by mass
・ Glutaric acid (multivalent carboxylic acid)
… 5.0% by mass
・ Succinic acid (multivalent carboxylic acid)
… 2.0% by mass
Orfin E1010 (surfactant) (acetylene glycol-based surfactant manufactured by Nissin Chemical Industry Co., Ltd.)
… 0.5% by mass
Pesresin A615GE (resin) (Aqueous dispersion of composite particles of polyester resin and acrylic resin manufactured by Takamatsu Oil & Fat Co., Ltd. (volume average particle size 40 nm))
… 10.0% by mass as the amount of resin particles
・ Water: The remaining amount is 100% by mass as a whole.

<Preparation of cyan ink>
Cyan ink having the following composition was prepared.

-Composition of cyan ink-
-Project Cyan APD1000 (manufactured by FUJIFILM Imaging Colorants, cyan pigment dispersion, pigment concentration: 12% by mass)
… 2.4% by mass as solid content
・ 1,2-Propanediol (manufactured by Wako Pure Chemical Industries, Ltd.) (water-soluble solvent)
… 20% by mass
-Orfin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) (surfactant)
… 1% by mass
-The following acrylic resin particles IA-1 (resin particles)
… 8% by mass as the amount of resin particles
・ Snowtex (registered trademark) XS (Nissan Chemical Industries, Ltd., colloidal silica)
… 0.06% by mass as the solid content of silica
・ Water: The remaining amount is 100% by mass as a whole.

(Preparation of aqueous dispersion of acrylic resin particles IA-1)
The acrylic resin particles IA-1 in the composition of the cyan ink were produced as follows.
560.0 g of methyl ethyl ketone was charged into a 2-liter three-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas introduction tube, and the temperature was raised to 87 ° C. Next, while maintaining the reflux state in the reaction vessel (hereinafter, the reflux state was maintained until the end of the reaction), 220.4 g of methyl methacrylate, 301.6 g of isobornyl methacrylate, and 58.0 g of methacrylic acid with respect to the methyl ethyl ketone in the reaction vessel. , 108 g of methyl ethyl ketone, and 2.32 g of "V-601" (polymerization initiator; dimethyl 2,2'-azobis (2-methylpropionate), manufactured by Wako Pure Chemical Industries, Ltd.), 2 The dropping was carried out at a constant velocity so that the dropping was completed in time. After the dropping was completed, the mixture was stirred for 1 hour, and then the operation of the following step (1) was performed on the solution after stirring for 1 hour.
Step (1) ... A solution consisting of 1.16 g of "V-601" and 6.4 g of methyl ethyl ketone was added, and the mixture was stirred for 2 hours.

Subsequently, the operation of the above step (1) was repeated 4 times, then a solution consisting of 1.16 g of "V-601" and 6.4 g of methyl ethyl ketone was further added, and stirring was continued for 3 hours (the operation up to this point was continued. "Reaction").
After completion of the reaction, the temperature of the solution was lowered to 65 ° C., 163.0 g of isopropanol was added, and the mixture was allowed to cool. A polymerization solution containing a polymer (solid content concentration 41.0%) was obtained.
The copolymer had a weight average molecular weight (Mw) of 63000 and an acid value of 65.1 (mgKOH / g).

Next, 317.3 g (solid content concentration 41.0% by mass) of the obtained polymerization solution was weighed, and 46.4 g of isopropanol and 1.65 g of a 20% maleic anhydride aqueous solution (water-soluble acidic compound, co-weight) were weighed. (Equivalent to 0.3% by mass of maleic acid) and 40.77 g of a 2 mol / L NaOH aqueous solution were added to the coalescence, and the temperature of the liquid in the reaction vessel was raised to 70 ° C.
Next, 380 g of distilled water was added dropwise to the solution heated to 70 ° C. at a rate of 10 ml / min to carry out water dispersion (dispersion step).
Then, by keeping the temperature of the liquid in the reaction vessel at 70 ° C. for 1.5 hours under reduced pressure, a total of 287.0 g of isopropanol, methyl ethyl ketone, and distilled water were distilled off (solvent removal step). To the obtained liquid, 0.278 g of Proxel GXL (S) (manufactured by Arch Chemicals Japan, Inc.) (440 ppm as benzoisothiazolin-3-one with respect to the polymer solid content) was added.
The obtained liquid was filtered through a 1 μm filter, and the filtrate was collected to obtain an aqueous dispersion of acrylic resin particles IA-1 having a solid content concentration of 26.5% by mass.
The glass transition temperature (Tg) of the acrylic resin particles IA-1 was 120 ° C., and the volume average particle size was 10 nm.
In this example, the aqueous dispersion of the acrylic resin particles IA-1 was used, and 8% by mass of the acrylic resin particles IA-1 was contained in the cyan ink as the amount of the resin particles.

<Evaluation>
The following evaluation was performed using the above-mentioned pretreatment liquid and ink.
The results are shown in Table 1.

(Precipitate)
FE2001 (polyethylene terephthalate (PET) base material, manufactured by Futamura Chemical Co., Ltd., thickness 25 μm, width 500 mm, length 2000 m) as a non-permeable base material is conveyed at 500 mm / sec, and the pretreatment liquid is transferred to a wire bar coater. It was applied so as to be 1.7 g / m ² (liquid application amount). The impermeable substrate coated with the pretreatment liquid was placed on a hot plate at 80 ° C., and the pretreatment liquid was dried for 30 seconds to form a layer derived from the pretreatment liquid. The impermeable substrate with a layer derived from the pretreatment liquid was wound into a roll so that the surface pressure was 50 kPa to obtain Roll 1. The obtained roll 1 was left at room temperature (25 ° C.) for 1 day.
The roll 1 is unwound, and the length in the length direction of the impermeable substrate is 29.7 cm from the point where the length of the impermeable substrate with a layer derived from the pretreatment liquid is about 1000 m, and it is not. Ten A4 size samples having a widthwise length of 21 cm of the permeable substrate were cut out.
The layer derived from the pretreatment liquid in the 10 cut pieces was visually observed to confirm the presence or absence of precipitates. Based on the confirmed results, the precipitates were evaluated according to the following evaluation criteria.
As for the precipitate, it was determined that the precipitate was generated when the following 1 or 2 was satisfied.
1. 1. 2. When impurities with a diameter of 1 mm or more are present in the layer derived from the pretreatment liquid. When a portion having a higher haze value than other portions is present in the layer derived from the pretreatment liquid In the following evaluation criteria, the rank in which the generation of precipitates is most suppressed is A.

-Evaluation criteria for precipitates-
A: No precipitate was visually recognized in all the samples (10 sheets).
B: Precipitates were visible in one of the 10 samples, but no precipitates were visible in the remaining samples.
C: Precipitates were visible in 2 to 4 of the 10 samples, but no precipitates were visible in the remaining samples.
D: Precipitates were visually recognized in 5 to 10 of the 10 samples.

(blocking)
In the evaluation of the precipitate, the same operation as the operation until the roll 1 was left at room temperature for 1 day was carried out.
The roll 1 is unwound, and the length in the length direction of the impermeable substrate is 29.7 cm from the point where the length of the impermeable substrate with a layer derived from the pretreatment liquid is about 1000 m, and it is not. Ten A4 size samples having a widthwise length of 21 cm of the permeable substrate were cut out.
The layer derived from the pretreatment liquid was visually observed in the 10 cut sheets, and the presence or absence of transfer marks (that is, transfer marks on the back surface of the PET substrate with respect to the surface surface of the layer derived from the pretreatment liquid) was confirmed. Based on the confirmed results, blocking was evaluated according to the following evaluation criteria.
In the following evaluation criteria, the rank in which the occurrence of blocking is most suppressed is A.

-Blocking evaluation criteria-
A: No transfer marks were visually recognized in all the samples (10 sheets).
B: Transfer marks were visible on 1 to 2 of the 10 samples, but not after transfer on the remaining samples.
C: Transfer marks were visually recognized on 3 to 10 of the 10 samples.

(Blur)
FE2001 (PET base material, manufactured by Futamura Chemical Co., Ltd., thickness 25 μm, width 500 mm, length 2000 m) as a non-permeable base material is conveyed at 500 mm / sec, and the pretreatment liquid is 1.7 g by a wire bar coater. It was applied so as to be / m ² (liquid application amount), and immediately after application, it was dried at 50 ° C. for 2 seconds to obtain a layer derived from the pretreatment liquid. A character image was recorded under the following image recording conditions by an inkjet method using the above-mentioned cyan ink on the layer derived from the obtained pretreatment liquid. As the character image, the character (unicode: U + 9DF9) shown in FIG. 2 was recorded at 2pt, 3pt, 4pt, and 5pt, respectively. Here, pt means a DTP point representing a font size, and 1 pt is 1/72 inch.
The obtained character image was observed, and the blurring of the image was evaluated according to the following evaluation criteria.
In the following evaluation criteria, the rank in which the blurring of the image is most suppressed is A.

-Image recording conditions-
Inkjet head: A 1,200 dpi (dot per inch, 1 inch is 2.54 cm) / 20 inch wide piezo full line head was used.
-Discharged droplet amount: 2.4 pL each.
The drive frequency was set to 30 kHz (base material transfer speed 635 mm / sec).

-Evaluation criteria for image blur-
A: 2pt characters could be reproduced.
B: 3pt characters could be reproduced, but 2pt characters could not be reproduced.
C: 4pt characters could be reproduced, but characters of 3pt or less could not be reproduced.
D: 4pt characters could not be reproduced.
Here, "reproducible" means the horizontal line represented by 1 in FIG. 3 and the horizontal line represented by 1 in FIG. 3 in the character image shown in FIG. 2 when confirmed from a place 0.5 m away. It means that the horizontal line represented by is separated.

[Examples 2 to 23, Comparative Examples 1 to 9]
The same operation as in Example 1 was performed except that the composition of the pretreatment liquid was changed as shown in Tables 1 and 2.
The results are shown in Tables 1 and 2.

In Tables 1 and 2, the numerical value in the column of each component means the mass% with respect to the total amount of the pretreatment liquid, and the blank means that the component is not contained.
The numerical value in the "resin" column means the amount of resin (solid content), not the amount of the aqueous dispersion of resin.

The details of the resins in Tables 1 and 2 are as follows.
・ SF300
... Superflex 300 (a water dispersion of polyurethane resin particles (volume average particle size 15 nm) manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.).
・ Acrylic LxA-1
… A water dispersion of acrylic resin particles prepared as follows.
・ PEG6000
… Polyethylene glycol 6000 (water-soluble resin that is a nonionic resin) (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

<Preparation of acrylic LxA-1 (aqueous dispersion of acrylic resin particles)>
In the preparation of the pretreatment liquid in Example 5, by using acrylic LxA-1 (aqueous dispersion liquid of acrylic resin particles), the pretreatment liquid contains 10.0% by mass of acrylic resin particles as the amount of resin particles. I let you.
Acrylic LxA-1 (aqueous dispersion of acrylic resin particles) was prepared as follows.
3.0 g of sodium dodecylbenzene sulfonate (62% by mass aqueous solution, manufactured by Tokyo Chemical Industry Co., Ltd.) and 376 g of water were added to a 1000 ml three-necked flask equipped with a stirrer and a cooling tube, and the mixture was heated to 90 ° C. under a nitrogen atmosphere. Solution A in which 11.0 g of a 50 mass% aqueous solution of sodium 2-acrylamide-2-methylpropanesulfonate (manufactured by Aldrich) in 20 g of water is dissolved in a mixed solution in a heated three-necked flask, and 2-hydroxymethacrylate. Ethyl (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) 12.5 g, 2- (2-ethoxyethoxy) ethyl acrylate (manufactured by Tokyo Kasei Kogyo Co., Ltd.) 5.0 g, benzyl acrylate (manufactured by Tokyo Kasei Kogyo Co., Ltd.) 17.0 g, And solution B in which 10.0 g of styrene (St; manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was mixed, and solution C in which 6.0 g of sodium persulfate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was dissolved in 40 g of water. It was dropped at the same time over time. After the completion of the dropping, the reaction was further carried out for 3 hours to obtain 500 g of acrylic LxA-1 (aqueous dispersion of acrylic resin particles) (solid content (that is, amount of acrylic resin particles): 10.1% by mass).
The glass transition temperature of the acrylic resin particles in the acrylic LxA-1 was 26 ° C., and the weight average molecular weight of the acrylic resin particles was 69000.

"PG" in the water-soluble solvent column in Tables 1 and 2 is propylene glycol.

As shown in Tables 1 and 2, a pretreatment liquid for a non-permeable substrate containing water and three or more kinds of carboxylic acids and having a ClogP of less than -1.00. In Examples 1 to 23 using the pretreatment liquid having a content of 2.0% by mass or less based on the total amount of the above, the generation of precipitates and the generation of blocking were suppressed.

The results of the comparative examples were as follows with respect to the examples.
In Comparative Examples 1 to 5 in which the types of carboxylic acids contained were 2 or less, the generation of precipitates could not be suppressed.
Further, in Comparative Examples 6 to 9 in which the content of the carboxylic acid having a ClogP of less than −1.00 was more than 2.0% by mass with respect to the total amount of the pretreatment liquid, the occurrence of blocking could not be suppressed.

From the results of Examples 11 and 22, when the total content of three or more kinds of carboxylic acids is 5.0% by mass or more with respect to the total amount of the pretreatment liquid (Example 11), the blurring of the image is further suppressed. It turns out that it will be done.
From the results of Examples 20 and 22, when the total content of three or more kinds of carboxylic acids is 13.0% by mass or less with respect to the total amount of the pretreatment liquid (Example 20), image blocking is further suppressed. It turns out that it will be done.

From the results of Examples 1 to 19, three or more kinds of carboxylic acids are
Polyvalent carboxylic acid A1, which is a polyvalent carboxylic acid having a ClogP of -1.00 or more and less than -0.50, and
Polyvalent carboxylic acid A2, which is a polyvalent carboxylic acid having a ClogP of -0.50 or more and -0.10 or less,
Polyvalent carboxylic acid A3, which is a polyvalent carboxylic acid having a ClogP of more than -0.10 and 0.50 or less,
(Examples 1 to 7, 11, 12, 13, and 19), it can be seen that the generation of precipitates is further suppressed.

From the results of Examples 1 to 6, in Examples 1 to 5, the pretreatment liquid contains the resin and the resin contains the resin particles, the pretreatment liquid contains the resin and the resin does not contain the resin particles. It can be seen that blocking and bleeding are more suppressed as compared with Example 6 containing the water-soluble resin (PEG6000).

S1 Impermeable base material W1 Unwinding device A1 Pretreatment liquid application device Dry1 Pretreatment liquid drying zone IJ1 Ink application device Dry2 Ink drying zone W2 Winding device 11, 12 Horizontal lines

Claims

A pretreatment liquid for a non-permeable substrate containing water and three or more kinds of carboxylic acids.
A pretreatment liquid for a non-permeable substrate in which the content of a carboxylic acid having a Clog P of less than −1.00 is 2.0% by mass or less based on the total amount of the pretreatment liquid for a non-permeable substrate.
The non-permeable according to claim 1, wherein the total content of the three or more kinds of carboxylic acids is 5.0% by mass to 13.0% by mass with respect to the total amount of the pretreatment liquid for a non-permeable substrate. Pretreatment liquid for base material.
The pretreatment liquid for a non-permeable substrate according to claim 1 or 2, wherein the weight average ClogP of the three or more kinds of carboxylic acids is 0.50 or less.
The pretreatment liquid for a non-permeable substrate according to any one of claims 1 to 3, wherein the weight average ClogP of the three or more kinds of carboxylic acids is −1.00 or more.
The pretreatment liquid for a non-permeable substrate according to any one of claims 1 to 4, wherein the three or more kinds of carboxylic acids contain two or more kinds of polyvalent carboxylic acids.
The above three or more kinds of carboxylic acids
Polyvalent carboxylic acid A1, which is a polyvalent carboxylic acid having a ClogP of -1.00 or more and less than -0.50, and
Polyvalent carboxylic acid A2, which is a polyvalent carboxylic acid having a ClogP of -0.50 or more and -0.10 or less,
Polyvalent carboxylic acid A3, which is a polyvalent carboxylic acid having a ClogP of more than -0.10 and 0.50 or less,
The pretreatment liquid for a non-permeable substrate according to any one of claims 1 to 5.
The content mass of the polyvalent carboxylic acid A1, which is a polyvalent carboxylic acid having a ClogP of -1.00 or more and less than -0.50, is defined as [A1].
The content mass of the polyvalent carboxylic acid A2, which is a polyvalent carboxylic acid having a ClogP of -0.50 or more and -0.10 or less, is defined as [A2].
When the content mass of the polyvalent carboxylic acid A3, which is a polyvalent carboxylic acid having a ClogP of more than -0.10 and 0.50 or less, is set to [A3].
The pretreatment liquid for a non-permeable substrate according to any one of claims 1 to 6, wherein the ratio of [A2] / ([A1] + [A3]) is 0.5 to 5.0.
Further, the pretreatment liquid for a non-permeable substrate according to any one of claims 1 to 7, which contains a resin.
The pretreatment liquid for a non-permeable substrate according to claim 8, wherein the resin contains resin particles.
The pretreatment liquid for a non-permeable substrate according to any one of claims 1 to 9,
Inks containing water and colorants,
Ink set with.
A step of applying the pretreatment liquid for a non-permeable base material according to any one of claims 1 to 9 to form a layer on the non-permeable base material.
A step of applying an ink containing a colorant and water to a part of the layer to record an image.
Image recording method having.
With a non-permeable substrate,
A layer arranged on the impermeable substrate and formed by the pretreatment liquid for an impermeable substrate according to any one of claims 1 to 9.
An image containing a colorant, which is partially arranged on the layer,
Image recordings provided with.
A method for producing a recording medium, which comprises a step of applying the pretreatment liquid for a non-permeable base material according to any one of claims 1 to 9 to form a layer on the non-permeable base material.
With a non-permeable substrate,
A layer arranged on the impermeable substrate and formed by the pretreatment liquid for an impermeable substrate according to any one of claims 1 to 9.
A recording medium comprising.