Film for latex ink

Abstract

The present invention addresses the problem of providing a film for a latex ink, the film having a latex-ink-receiving layer that is excellent in terms of both ink adhesion and abrasion resistance. This problem is solved by providing a film for a latex ink, the film having a layered structure in which a latex-ink-receiving layer (X) and a substrate (Y) are layered. The latex-ink-receiving layer (X) is formed from a resin composition (x1) comprising an acrylic resin (A) having a crosslinkable functional group, a prescribed crosslinking agent (B), a prescribed UV-curable acrylate compound (C), and a photopolymerization initiator (D).

Description

Latex ink film

[0001] The present invention relates to a film for latex inks.

[0002] In recent years, printing methods using latex ink have been attracting attention (see, for example, Patent Document 1). Unlike solvent inks in which a pigment is dissolved in an organic solvent, latex inks are aqueous inks in which a pigment is dispersed in water together with latex (a polymer). Therefore, there is no emission of volatile organic compounds (VOCs) resulting from organic solvents, which is a problem when using solvent inks. Therefore, printed materials using latex inks have the advantage that they can be used safely in a variety of locations, such as restaurants, educational institutions, medical institutions, and commercial facilities.

[0003] Taking these advantages into consideration, the present applicant has proposed a film for latex ink in Patent Document 2. The film for latex ink described in Patent Document 2 includes a substrate and a printing coating layer to which latex ink is applied. The printing coating layer contains a material having a structure in which a polymeric material whose constituent monomers are vinyl chloride, vinyl acetate, and a crosslinkable monomer is crosslinked with a crosslinking agent. This results in a film for latex ink having a printing coating layer that has excellent adhesion to both the portion printed with latex ink and the substrate.

[0004] The "printing coating layer" in Patent Document 2 is referred to as the "latex ink-receiving layer" in this specification. That is, the "latex ink-receiving layer" refers to a layer to which latex ink is applied and which has the function of fixing the printed portion of the applied latex ink.

[0005] JP 2016-120719 A JP 2019-172877 A

[0006] In recent years, printing methods using latex inks have been widely adopted, and various requirements have been increasing for the latex ink-receiving films used in such methods. Specifically, from the viewpoint of preventing scratches on the surface of the latex ink-receiving layer, the latex ink-receiving layer of the latex ink-receiving film may be required to have abrasion resistance.

[0007] However, in order to ensure adhesion of the latex ink-receiving layer to the area printed with latex ink (hereinafter simply referred to as "ink adhesion"), the latex ink-receiving layer needs to have a certain degree of softness. As a result, the surface of the latex ink-receiving layer is easily scratched and has poor abrasion resistance. For these reasons, the "printing coating layer" in Patent Document 2 also has poor abrasion resistance. Thus, there is a problem in that it is difficult to achieve both ink adhesion and abrasion resistance in a latex ink-receiving layer.

[0008] Furthermore, latex ink films are sometimes applied to glass surfaces in stores, showrooms, offices, and the like for advertising and decorative purposes. When applying a latex ink film to a substrate such as a glass surface, water or an aqueous solution containing a surfactant is sprayed onto the application surface (adhesive layer surface) of the latex ink film or the mating surface of the substrate to prevent air from getting between the latex ink film and the substrate. After the two films are brought into close contact and positioned, a so-called wet application method is generally used, in which water or an aqueous solution containing a surfactant is used to scrape the water and air from the latex ink film side using a squeegee. In this case, to improve the slipperiness of the squeegee, the aqueous solution may also be sprayed onto the latex ink-receiving layer side, which is the side opposite the adhesive layer. Therefore, the latex ink-receiving layer of a latex ink-receiving film to be applied with water must maintain adhesion to the latex ink-printed portion of the latex ink-receiving layer even when rubbed with a squeegee while in contact with water (hereinafter, this will also be referred to as "water-resistant ink adhesion").

[0009] The present invention has been made in consideration of such problems, and an object of the present invention is to provide a film for latex ink that has excellent ink adhesion and water-resistant ink adhesion while ensuring abrasion resistance.

[0010] As a result of extensive research aimed at solving the above-mentioned problems, the present inventors have discovered that a latex ink-receiving layer formed from a resin composition containing an acrylic resin having a crosslinkable functional group, a specific crosslinking agent, a specific ultraviolet-curable acrylate compound, and a photopolymerization initiator can solve the above-mentioned problems. Based on this discovery, the present inventors have conducted further research and have completed the present invention. Specifically, the present invention relates to the following items [1] to [8]. [1] A laminated structure in which a latex ink receiving layer (X) and a substrate (Y) are laminated, the latex ink receiving layer (X) being formed from a resin composition (x1) containing an acrylic resin (A) having a crosslinkable functional group, a crosslinking agent (B), an ultraviolet-curable acrylate compound (C) which is an ester of an alkylene oxide-modified polyol compound and (meth)acrylic acid, and a photopolymerization initiator (D), the crosslinking agent (B) containing an isocyanurate compound (B1), the isocyanurate compound (B1) containing an isocyanurate compound (B1-1) and a modified isocyanurate compound (B1-2), the isocyanurate compound (B1-1) being a trimer of 1,6-hexamethylene diisocyanate, A film for latex inks, wherein the modified isocyanurate compound (B1-2) is a trimer of 1,6-hexamethylene diisocyanate and has one or more tertiary amino groups. [2] The film for latex inks according to the above item [1], wherein the substrate (Y) contains a polyester resin. [3] The film for latex inks according to the above item [1] or [2], wherein the latex ink-receiving layer (X) is laminated on one surface of the substrate (Y), and a pressure-sensitive adhesive layer (Z) is provided on the other surface of the substrate (Y). [4] The film for latex inks according to the above item [3], wherein the adhesive surface of the pressure-sensitive adhesive layer (Z) is covered with a release liner. [5] The film for latex inks according to any one of the above items [1] to [4], which is used for printing using a latex ink containing an acrylic resin. [6] A method of using the film for latex ink according to any one of [1] to [5] above, for forming a printed portion on the latex ink-receiving layer of the film for latex ink using latex ink.[7] A method for producing a printed matter, comprising a step of forming a printed portion using latex ink on the latex ink-receiving layer of the film for latex ink described in any one of [1] to [5] above. [8] A printed matter having a printed portion printed with latex ink on the latex ink-receiving layer of the film for latex ink described in any one of [1] to [5] above.

[0011] According to the present invention, it is possible to provide a film for latex ink that has excellent ink adhesion and water-resistant ink adhesion while ensuring scratch resistance.

[0012] 1 is a cross-sectional view showing one embodiment of a film for latex ink of the present invention.

[0013] As used herein, the term "active ingredient" refers to the components contained in the target composition, excluding diluting solvents such as water and organic solvents. In addition, as used herein, "(meth)acrylic acid" refers to both "acrylic acid" and "methacrylic acid." Furthermore, "(meth)acryloyl group" refers to both "acryloyl group" and "methacryloyl group." Furthermore, as used herein, for preferred numerical ranges (e.g., ranges of content, etc.), the lower and upper limits described in stages can be independently combined. For example, the description "preferably 10 to 90, more preferably 30 to 60" can be combined with the "preferable lower limit (10)" and the "more preferred upper limit (60)" to yield "10 to 60." Furthermore, as used herein, the numerical values ​​in the examples are numerical values ​​that can be used as upper or lower limits.

[0014] [Embodiments of the Latex Ink Film of the Present Invention] The latex ink film of the present invention has a laminated structure in which a latex ink-receiving layer (X) and a substrate (Y) are laminated together. The latex ink-receiving layer (X) is formed from a resin composition (x1) containing an acrylic resin (A) having a crosslinkable functional group, a crosslinking agent (B), an ultraviolet-curable acrylate compound (C) which is an ester of an alkylene oxide-modified polyol compound and (meth)acrylic acid, and a photopolymerization initiator (D). The crosslinking agent (B) contains an isocyanurate compound (B1). The isocyanurate compound (B1) contains an isocyanurate compound (B1-1) and a modified isocyanurate compound (B1-2). The isocyanurate compound (B1-1) is a trimer of 1,6-hexamethylene diisocyanate, and the modified isocyanurate compound (B1-2) is a trimer of 1,6-hexamethylene diisocyanate and has one or more tertiary amino groups.

[0015] As a result of extensive investigations, the present inventors have found that a latex ink-receiving layer formed from a resin composition (x1) containing "an acrylic resin (A) having a crosslinkable functional group," "a crosslinking agent (B) containing an isocyanurate compound (B1)," "an ultraviolet-curable acrylate compound (C) which is an ester of an alkylene oxide-modified polyol compound and (meth)acrylic acid," and "a photopolymerization initiator (D)," has excellent ink adhesion and water-resistant ink adhesion while ensuring scratch resistance. Furthermore, through extensive investigations, the present inventors have completed the present invention.

[0016]

[0023] The following provides a detailed description of the latex ink film of the present invention, including its configuration, components constituting the latex ink film (substrate, latex ink-receiving layer, pressure-sensitive adhesive layer, and release liner), a method for producing the latex ink film, and uses of the latex ink film. In the following description, the "ultraviolet-curable acrylate compound (C), which is an ester of an alkylene oxide-modified polyol compound and (meth)acrylic acid" may also be abbreviated as "ultraviolet-curable acrylate compound (C)."

[0017] [Configuration of Film for Latex Ink] The film for latex ink of the present invention has a laminated structure in which a latex ink-receiving layer (X) and a substrate (Y) are laminated.

[0018] Figure 1 shows a schematic cross-sectional view of one embodiment of the latex ink film of the present invention. The latex ink film 1 shown in Figure 1 has a laminate structure in which a latex ink-receiving layer (X) is laminated on one surface (Ya) of a substrate (Y). Here, as shown in Figure 1, the latex ink film of one embodiment of the present invention preferably has a pressure-sensitive adhesive layer (Z) provided on the other surface (Yb) of the substrate (Y). This allows the latex ink film to be suitably used as a pressure-sensitive adhesive film.

[0019] Although not shown, the adhesive surface of the pressure-sensitive adhesive layer (Z) may be covered with a release liner. The release liner may be peeled off when the pressure-sensitive adhesive layer (Z) is attached to an adherend, thereby exposing the adhesive surface of the pressure-sensitive adhesive layer (Z). Although not shown, a latex ink-receiving layer (X) may be provided on both the one surface (Ya) and the other surface (Yb) of the substrate (Y) without providing the pressure-sensitive adhesive layer (Z). Although not shown, another layer may be provided between the latex ink-receiving layer (X) and the substrate (Y). Examples of such another layer include an easy-adhesion layer.

[0020] [Components Constituting the Latex Ink Film] The latex ink film of the present invention has a latex ink-receiving layer (X) and a substrate (Y). As described above, the latex ink film of one embodiment of the present invention may further have a pressure-sensitive adhesive layer (Z) in addition to the latex ink-receiving layer (X) and the substrate (Y). In addition to the latex ink-receiving layer (X) and the substrate (Y), it may further have a pressure-sensitive adhesive layer (Z) and a release liner. The latex ink-receiving layer (X), the substrate (Y), the pressure-sensitive adhesive layer (Z), and the release liner are described in detail below.

[0021] <Latex ink-receiving layer (X)> The latex ink film of the present invention has a latex ink-receiving layer (X). The latex ink-receiving layer (X) is the portion to which latex ink is applied and has the function of fixing the printed portion of the applied latex ink. The thickness of the latex ink-receiving layer (X) is not particularly limited, but is preferably 0.05 μm to 50 μm, more preferably 0.1 μm to 25 μm, and even more preferably 0.1 μm to 10 μm.

[0022] The latex ink-receiving layer (X) is formed from a resin composition (x1) containing an acrylic resin (A) having a crosslinkable functional group, a crosslinking agent (B), an ultraviolet-curable acrylate compound (C), and a photopolymerization initiator (D). By forming the resin composition (x1) from the resin composition (x1) containing the acrylic resin (A) having a crosslinkable functional group, the crosslinking agent (B), the ultraviolet-curable acrylate compound (C), and the photopolymerization initiator (D), a crosslinked structure formed by the reaction between the acrylic resin (A) having a crosslinkable functional group and the crosslinking agent (B) and a polymer structure formed between the ultraviolet-curable acrylate compound (C) and the photopolymerization initiator (D) are mixed on the surface of the latex ink-receiving layer (X). This improves ink adhesion and abrasion resistance. In addition, by using an ester of an alkylene oxide-modified polyol compound and (meth)acrylic acid as the UV-curable acrylate compound (C), the distance between the (meth)acryloyl groups, which are the UV-curable moieties, is increased, thereby appropriately reducing the hardness of the latex ink-receiving layer (X). This reduces the force applied to the latex ink-receiving layer (X) when rubbed with a squeegee during wet application, making the ink less likely to peel off during wet application. In other words, the water-resistant adhesion of the ink is improved. Although there was concern that a decrease in the hardness of the latex ink-receiving layer (X) would reduce its abrasion resistance, the presence of a polymer structure formed by the UV-curable acrylate compound (C) and the photopolymerization initiator (D) on the surface of the latex ink-receiving layer (X) improves abrasion resistance, ensuring sufficient abrasion resistance. It is presumed that the combined use of these factors results in the formation of a latex ink-receiving layer (X) that is excellent in both ink adhesion and water-resistant ink adhesion while ensuring scratch resistance.

[0023] In the following description, the "acrylic resin (A) having a crosslinkable functional group," the "crosslinking agent (B)," the "ultraviolet-curable acrylate compound (C)," and the "photopolymerization initiator (D)" will also be referred to as "component (A)," "component (B)," "component (C)," and "component (D)," respectively.

[0024] In one embodiment of the present invention, the resin composition (x1) that is the material for forming the latex ink-receiving layer (X) may be composed only of component (A), component (B), component (C), and component (D), or may contain components other than component (A), component (B), component (C), and component (D) in addition to component (A), component (B), component (C), and component (D), provided that the effects of the present invention are not impaired. Examples of such components include additives for ink-receiving layers that are commonly used in ink-receiving layers such as latex ink-receiving layers, such as reaction accelerators (catalysts), surface conditioners, plasticizers, fillers, and colorants.

[0025] In one embodiment of the present invention, the total content of component (A), component (B), component (C), and component (D) is preferably 80% by mass to 100% by mass, more preferably 85% by mass to 100% by mass, and even more preferably 90% by mass to 100% by mass, based on the total amount of active components of resin composition (x1).

[0026] The acrylic resin (A) having a crosslinkable functional group, the crosslinking agent (B), the ultraviolet-curable acrylate compound (C), and the photopolymerization initiator (D) contained in the resin composition (x1) will be described in detail below.

[0027] (Acrylic Resin (A) Having Crosslinkable Functional Group) The resin composition (x1) used in the present invention contains an acrylic resin (A) having a crosslinkable functional group. The acrylic resin (A) having a crosslinkable functional group is preferably an acrylic resin (A1) having a structural unit (a1) derived from a crosslinkable functional group-containing monomer (a1′) (hereinafter also referred to as monomer (a1′)).

[0028] Examples of the crosslinkable functional group possessed by the monomer (a1') include one or more selected from a hydroxyl group, a carboxyl group, an amino group, and an epoxy group. That is, examples of the monomer (a1') include a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an amino group-containing monomer, and an epoxy group-containing monomer. Examples also include a monomer containing two or more crosslinkable functional groups selected from a hydroxyl group, a carboxyl group, an amino group, and an epoxy group. These monomers (a1') may be used alone or in combination of two or more. Among these, hydroxyl group-containing monomers and carboxyl group-containing monomers are preferred as the monomer (a1').

[0029] Examples of the hydroxyl group-containing monomer include hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; N-methylol acrylamide; ε-caprolactone-modified hydroxy(meth)acrylate; and carbonate-modified (meth)acrylate.

[0030] Examples of the carboxy group-containing monomer include (meth)acrylic acid; and compounds obtained by reacting the terminal hydroxyl group of the hydroxy group-containing monomer described above with an acid anhydride such as one or more aliphatic dicarboxylic acids selected from succinic anhydride, glutaric anhydride, and the like.

[0031] Here, the acrylic resin (A) having a crosslinkable functional group may be an acrylic copolymer (A2) having a structural unit (a2) derived from an alkyl (meth)acrylate (a2') (hereinafter also referred to as "monomer (a2')") together with the crosslinkable functional group-containing monomer (a1').

[0032] The number of carbon atoms in the alkyl group of the monomer (a2') is preferably 1 to 24. From the viewpoint of adjusting the glass transition temperature (Tg) of the acrylic resin (A) within an appropriate range and thereby making it easier to exhibit ink adhesion, the number of carbon atoms in the alkyl group is preferably 2 to 20. The alkyl group of the monomer (a2') may be a linear alkyl group or a branched alkyl group.

[0033] Examples of the monomer (a2') include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, and stearyl (meth)acrylate. These monomers (a2') may be used alone or in combination of two or more.

[0034] In the acrylic copolymer (A2) containing the structural unit (a2), the content of the structural unit (a2) is preferably from 1 to 99 mass%, more preferably from 5 to 95 mass%, and even more preferably from 10 to 90 mass%, based on the total amount of the acrylic copolymer (A2).

[0035] The acrylic resin (A1) and the acrylic copolymer (A2) may be an acrylic copolymer (A3) further having a structural unit (a3) ​​derived from a monomer (a3') other than the monomers (a1') and (a2').

[0036] Examples of the monomer (a3′) include olefins such as ethylene, propylene, and isobutylene; halogenated olefins such as vinyl chloride and vinylidene chloride; diene monomers such as butadiene, isoprene, and chloroprene; (meth)acrylates having a cyclic structure such as cyclohexyl (meth)acrylate, benzyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, and imide (meth)acrylate; styrene, α-methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, acrylonitrile, (meth)acrylamide, (meth)acrylonitrile, (meth)acryloylmorpholine, and N-vinylpyrrolidone.

[0037] In the acrylic copolymer (A3) containing the structural unit (a3), the content of the structural unit (a3) ​​is preferably from 1 to 99 mass%, more preferably from 5 to 95 mass%, and even more preferably from 10 to 90 mass%, based on the total amount of the acrylic copolymer (A3).

[0038] The molecular weight of the acrylic resin (A) having a crosslinkable functional group is not particularly limited, but the number average molecular weight is preferably 3,000 to 100,000. The number average molecular weight is a polystyrene-equivalent value measured by gel permeation chromatography (GPC) using a differential refractometer.

[0039] Here, the hydroxyl value of the acrylic resin (A) having a crosslinkable functional group is preferably 5.0 mgKOH / g to 25.0 mgKOH / g, more preferably 6.0 mgKOH / g to 24.0 mgKOH / g, and even more preferably 7.0 mgKOH / g to 23.0 mgKOH / g. When the hydroxyl value of the acrylic resin (A) having a crosslinkable functional group is equal to or greater than the above-mentioned lower limit, ink adhesion is easily improved. Furthermore, the stability of the latex ink-receiving layer is easily improved. When the hydroxyl value of the acrylic resin (A) having a crosslinkable functional group is equal to or less than the above-mentioned upper limit, the stability of the coating liquid (a solution containing the resin composition (x1)) used in forming the latex ink-receiving layer (X) is easily improved. Note that, in this specification, the hydroxyl value of the acrylic resin (A) having a crosslinkable functional group means a value measured in accordance with JIS K0070:1992.

[0040] The acid value of the acrylic resin (A) having a crosslinkable functional group is preferably 10.0 mgKOH / g or less, more preferably 1.0 mgKOH / g to 9.0 mgKOH / g, and even more preferably 2.0 mgKOH / g to 8.0 mgKOH / g. In this specification, the acid value of the acrylic resin (A) having a crosslinkable functional group means a value measured in accordance with JIS K0070:1992.

[0041] The glass transition temperature (Tg) of the acrylic resin (A) having a crosslinkable functional group is preferably 100°C or lower, more preferably 95°C or lower, and even more preferably 90°C or lower, from the viewpoint of further improving ink adhesion. In particular, when the glass transition temperature (Tg) of the acrylic resin (A) having a crosslinkable functional group is lower than the curing temperature of the latex ink, ink adhesion is more likely to be further improved. Furthermore, the glass transition temperature (Tg) of the acrylic resin (A) having a crosslinkable functional group is usually 30°C or higher, preferably 40°C or higher, and more preferably 50°C or higher, from the viewpoint of further improving sticking resistance. Here, "sticking resistance" means "the property of suppressing sticking between the latex ink-receiving layer (X) and the back surface of the substrate (Y) when the laminate is wound up in the process of forming the latex ink-receiving layer (X) on the surface of the substrate (Y) and producing a laminate of the substrate (Y) and the latex ink-receiving layer (X)." In this specification, the glass transition temperature (Tg) of the acrylic resin (A) having a crosslinkable functional group means a value measured in accordance with JIS K 7121:1987 using a differential scanning calorimeter (manufactured by TA Instruments Japan, product name "DSC Q2000") at a heating rate of 20°C / min.

[0042] (Crosslinking Agent (B)) The resin composition (x1) used in the present invention contains a crosslinking agent (B). The crosslinking agent (B) contains an isocyanurate compound (B1). If the crosslinking agent (B) does not contain the isocyanurate compound (B1), the ink adhesion of the latex ink-receiving layer (X) cannot be improved. In the present invention, it is presumed that the use of a crosslinking agent (B) containing an isocyanurate compound (B1) results in a crosslinked structure formed by reaction with the acrylic resin (A) having a crosslinkable functional group, which contributes to ink adhesion and results in excellent ink adhesion. Furthermore, if the crosslinking agent (B) does not contain the isocyanurate compound (B1), the adhesion between the latex ink-receiving layer (X) and the substrate (Y) cannot be ensured. It is presumed that by using the crosslinking agent (B) containing the isocyanurate compound (B1), due to the influence of the polar group of the isocyanurate compound (B1), a latex ink receiving layer (X) having a crosslinked structure is formed that exhibits excellent adhesion to the substrate (Y), particularly to a substrate (Y) containing a polyester resin such as polyethylene terephthalate.

[0043] In one embodiment of the present invention, the content of the isocyanurate compound (B1) is preferably 50% by mass to 100% by mass, more preferably 70% by mass to 100% by mass, even more preferably 80% by mass to 100% by mass, and still more preferably 90% by mass to 100% by mass, based on the total amount of the crosslinking agent (B), from the viewpoint of further improving ink adhesion. The isocyanurate compound (B1) will be described in detail below.

[0044] (Isocyanurate Compound (B1)) In the present invention, the isocyanurate compound (B1) includes an isocyanurate compound (B1-1) and a modified isocyanurate compound (B1-2). From the viewpoint of further improving ink adhesion, the total content of the isocyanurate compound (B1-1) and the modified isocyanurate compound (B1-2) in the isocyanurate compound (B1) is preferably 80% by mass to 100% by mass, more preferably 90% by mass to 100% by mass, and even more preferably 95% by mass to 100% by mass, based on the total amount of the isocyanurate compound (B1).

[0045] —Isocyanurate Compound (B1-1)— The isocyanurate compound (B1) includes an isocyanurate compound (B1-1), which is a trimer of 1,6-hexamethylene diisocyanate, and specifically, is a compound represented by the following formula (1):

[0046] - Isocyanurate Compound (B1-2) - The isocyanurate compound (B1) includes a modified isocyanurate compound (B1-2). The modified isocyanurate compound (B1-2) is a trimer of 1,6-hexamethylene diisocyanate and has one or more tertiary amino groups.

[0047] An example of a method for introducing one or more tertiary amino groups into the compound of formula (1) to form a modified product is a method of reacting a modifying agent having a hydroxyl group and a tertiary amino group with the compound of formula (1). Examples of such modifiers include N,N-dimethylaminohexanol (e.g., Kao Riser No. 25, manufactured by Kao Corporation), N,N-dimethylaminoethoxyethoxyethanol (e.g., Kao Riser No. 23NP, manufactured by Kao Corporation), N,N-dimethylaminoethoxyethanol (e.g., Kao Riser No. 26, manufactured by Kao Corporation), N,N,N'-trimethylaminoethylethanolamine (e.g., TOYOCAT RX5, manufactured by Tosoh Corporation), 2-[[3-(dimethylamino)propyl]methylamino]ethanol (e.g., POLYCAT 17, manufactured by Evonik), and N,N-dimethylethanolamine (e.g., JEFFCAT DMEA, manufactured by Huntsman). The modifier may have a ring structure, but is preferably a compound as described above that does not have a ring structure. The modifier is preferably an organic non-metallic compound as described above that does not contain a metal element. That is, the modifying agent is preferably an acyclic organic non-metallic compound having a hydroxyl group and a tertiary amino group.

[0048] The reaction of the compound of formula (1) with the modifier is preferably carried out, for example, by charging the compound of formula (1) and the modifier into a nitrogen-substituted reaction vessel and stirring at a reaction temperature of 60°C to 100°C for 1 hour to 5 hours.

[0049] - Preparation of Isocyanurate Compound (B1) - The isocyanurate compound (B1) can be prepared, for example, by appropriately adjusting the ratio of the amounts of the compound of formula (1) and the modifier added to a reaction vessel when reacting the compound of formula (1) with the modifier described above. The ratio of the modifier added to the compound of formula (1) is preferably 0.01 to 10 parts by mass, and more preferably 0.05 to 5 parts by mass, per 100 parts by mass of the compound of formula (1). This results in only a portion of the numerous compounds of formula (1) having one or more tertiary amino groups, making it possible to prepare an isocyanurate compound (B1) containing the isocyanurate compound (B1-1) and a modified isocyanurate compound (B1-2). The content of the modified isocyanurate compound (B1-2) is preferably 0.5 mol % to 10 mol %, more preferably 1 mol % to 5 mol %, based on the total amount of the isocyanurate compound (B1).

[0050] (Content of Crosslinking Agent (B)) From the viewpoint of making it easier to exhibit the effects of the present invention, the content of the crosslinking agent (B) is preferably 3.0 parts by mass or more, more preferably 5.0 parts by mass or more, and even more preferably 7.0 parts by mass or more, relative to 100 parts by mass of the acrylic resin (A) having a crosslinkable functional group, and is also preferably 40 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 20 parts by mass or less.

[0051] (UV-Curable Acrylate Compound (C)) The resin composition (x1) used in the present invention contains a UV-curable acrylate compound (C), which is a component that can be cured (polymerized) by irradiation with UV light. The UV-curable acrylate compound (C) is an ester of an alkylene oxide-modified polyol compound and (meth)acrylic acid. When an ester of a non-alkylene oxide-modified polyol compound and (meth)acrylic acid is used, the water-resistant adhesion of the ink to the latex ink-receiving layer (X) cannot be improved. The UV-curable acrylate compound (C) may be used alone or in combination of two or more.

[0052] From the viewpoint of improving abrasion resistance, the alkylene oxide-modified polyol compound constituting the ultraviolet-curable acrylate compound (C) is preferably an alkylene oxide-modified product of a divalent to decavalent polyol, more preferably an alkylene oxide-modified product of a trivalent to hexavalent polyol, even more preferably an alkylene oxide-modified product of a tetravalent to hexavalent polyol, and even more preferably an alkylene oxide-modified product of a hexavalent polyol. The number of carbon atoms in the alkylene oxide-modified product is preferably 2 to 4, more preferably 2 to 3, and even more preferably 2.

[0053] Examples of polyols constituting the alkylene oxide-modified polyol compound include trimethylolethane, trimethylolpropane, trimethylolbutane, ditrimethylolpropane, tritrimethylolpropane, pentaerythritol, dipentaerythritol, tripentaerythritol, glycerin, polyglycerin, 1,3,5-pentanetriol, sorbitol, adonitol, arabitol, xylitol, and mannitol. Among these, from the viewpoint of improving the effects of the present invention, pentaerythritol and dipentaerythritol are preferred, and dipentaerythritol is more preferred.

[0054] The number of alkylene oxides in one molecule of the ultraviolet-curable acrylate compound (C) (in other words, the number of alkylene oxides in one molecule of the alkylene oxide-modified polyol compound) is preferably 2 to 34, more preferably 3 to 20, and even more preferably 4 to 16, from the viewpoint of improving abrasion resistance.

[0055] From the viewpoint of improving the effects of the present invention, the number of (meth)acryloyl groups in the ultraviolet-curable acrylate compound (C) is preferably 2 or more, more preferably 2 to 6. The ultraviolet-curable acrylate compound (C) may be a complete ester or a partial ester, but is preferably a complete ester.

[0056] Here, from the viewpoint of making it easier to improve the effects of the present invention, it is preferable that the ultraviolet-curable acrylate compound (C) contains one or more compounds selected from the group consisting of compounds represented by the following general formula (2) and compounds represented by the following general formula (3):

[0057]

[0058] In the above general formula (2), X is -R １ It represents an O- group. １ R in the O-group １ is preferably an alkylene group having 2 to 4 carbon atoms, more preferably an alkylene group having 2 to 3 carbon atoms, and even more preferably an alkylene group having 2 carbon atoms (ethylene group). a, b, c, d, e, and f each represent -R １ The value of a+b+c+d+e+f is preferably 2 to 34, more preferably 3 to 20, even more preferably 4 to 16, still more preferably 6 to 16, even more preferably 8 to 16, and even more preferably 10 to 16. When a+b+c+d+e+f is 2 or more, a plurality of -R １ The O- may be the same or different, but it is preferable that they are the same from the viewpoint of ease of availability of the compound.

[0059]

[0060] In the above general formula (3), Y is -R ２It represents an O- group. ２ R in the O-group ２ is preferably an alkylene group having 2 to 4 carbon atoms, more preferably an alkylene group having 2 to 3 carbon atoms, and even more preferably an alkylene group having 2 carbon atoms (ethylene group). g, h, i, and j each represent -R ２ The value of g+h+i+j is preferably 2 to 34, more preferably 3 to 20, even more preferably 4 to 16, still more preferably 4 to 12, even more preferably 4 to 10, and even more preferably 4 to 8. When g+h+i+j is 2 or more, a plurality of -R ２ The O- may be the same or different, but it is preferable that they are the same from the viewpoint of ease of availability of the compound.

[0061] Among the compounds represented by the general formula (2) and the compounds represented by the general formula (3), from the viewpoint of improving abrasion resistance, it is preferable that the ultraviolet-curable acrylate compound (C) contains a compound represented by the general formula (1).

[0062] (Photopolymerization initiator (D)) As the photopolymerization initiator (D), a general photopolymerization initiator used when curing the ultraviolet-curable acrylate compound (C) with ultraviolet light can be used as appropriate. Specific examples include 1-hydroxycyclohexyl phenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyl diphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, benzyl, dibenzyl, diacetyl, β-chloroanthraquinone, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylzoyldiphenylphosphine oxide, and bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide.

[0063] The content of the photopolymerization initiator (D) is preferably 0.1 to 10 parts by mass based on 100 parts by mass of the ultraviolet-curable acrylate compound (C).

[0064] (Total Content of Acrylic Resin (A) Having Crosslinkable Functional Group and UV-Curable Acrylate Compound (C)) In one embodiment of the present invention, the total content of the acrylic resin (A) having a crosslinkable functional group and the UV-curable acrylate compound (C) is, from the viewpoint of making it easier to exhibit the effects of the present invention, preferably 80% by mass or more, more preferably 85% by mass or more, and even more preferably 90% by mass or more, relative to the total content (100% by mass) of the acrylic resin (A) having a crosslinkable functional group, the crosslinking agent (B), the UV-curable acrylate compound (C), and the photopolymerization initiator (D). Also, it is preferably 97% by mass or less, more preferably 95% by mass or less.

[0065] (Content Ratio of Acrylic Resin (A) Having Crosslinkable Functional Group and Ultraviolet-Curable Acrylate Compound (C)) In one embodiment of the present invention, the content ratio of the acrylic resin (A) having a crosslinkable functional group and the ultraviolet-curable acrylate compound (C) [(A) / (C)] is, in mass ratio, preferably 2 / 98 to 70 / 30, more preferably 3 / 97 to 50 / 50, even more preferably 4 / 96 to 30 / 70, still more preferably 5 / 95 to 20 / 80, and even more preferably 5 / 95 to 16 / 84, from the viewpoint of forming a latex ink-receiving layer (X) having superior abrasion resistance. According to one aspect of the present invention, even if the amount of crosslinked structures formed by the acrylic resin (A) having a crosslinkable functional group and the crosslinking agent (B) in the latex ink-receiving layer (X) is very small compared to the polymer structure formed by the ultraviolet-curable acrylate compound (C) and the photopolymerization initiator (D), it is possible to ensure excellent ink adhesion and water-resistant ink adhesion while maintaining abrasion resistance.

[0066] <Substrate (Y)> The film for latex ink of the present invention has a substrate (Y). The substrate (Y) supports the latex ink-receiving layer (X) and also functions as a support for supporting a printed portion formed on the latex ink-receiving layer (X).

[0067] The substrate (Y) is not particularly limited, but is preferably a resin film. The substrate (Y) being a resin film improves the rigidity and flexibility of the film for latex ink, thereby improving the handling properties of the film for latex ink. This is also advantageous from the viewpoint of reducing the production cost and weight of the film for latex ink.

[0068] Here, the substrate (Y) is preferably a transparent resin film, which allows a printed matter having a printed portion formed on the latex ink-receiving layer of the film for latex ink to be suitably used as glass decoration in stores, showrooms, offices, etc.

[0069] Examples of resins constituting the resin film include polyester-based resins such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyolefin resins such as polyethylene and polypropylene; polystyrene; acrylonitrile-butadiene-styrene copolymer; cellulose triacetate; polycarbonate; urethane resins such as polyurethane and acrylic-modified polyurethane; polymethylpentene; polysulfone; polyether ether ketone; polyethersulfone; polyphenylene sulfide; polyimide-based resins such as polyetherimide and polyimide; polyamide-based resins; acrylic resins; fluorine-based resins, etc. Among these, from the viewpoint of easily improving the adhesion between the latex ink-receiving layer (X) and the substrate (Y), polyester-based resins and polyolefin-based resins are preferred, polyester-based resins are more preferred, and polyethylene terephthalate is even more preferred.

[0070] The resin film may be composed of only one type of resin, or may be composed of two or more types of resin. When the resin film is composed of two or more types of resin, it is preferably a multi-layered structure. Furthermore, from the viewpoint of easily improving the adhesion between the latex ink-receiving layer (X) and the substrate (Y), the uppermost layer of the multi-layered structure (the layer in contact with the latex ink-receiving layer) is preferably a polyester-based resin, more preferably polyethylene terephthalate.

[0071] The resin film may be unstretched or may be stretched uniaxially, such as longitudinally or transversely, or biaxially.

[0072] In addition, the resin film may contain, together with these resins, additives for the substrate, such as a surface conditioner, a plasticizer, an ultraviolet absorber, a light stabilizer, a colorant, etc. The content of the additives for the substrate is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 3% by mass or less, based on the total amount of the substrate (Y).

[0073] The thickness of the substrate (Y) is not particularly limited, but is preferably 15 μm to 300 μm, more preferably 30 μm to 200 μm.

[0074] <Adhesive Layer (Z)> The film for latex ink of one embodiment of the present invention may have an adhesive layer (Z). By having the adhesive layer (Z), the film for latex ink of one embodiment of the present invention can be suitably used as an adhesive film.

[0075] The adhesive constituting the adhesive layer is not particularly limited, and examples thereof include acrylic adhesives, urethane adhesives, and silicone adhesives.

[0076] The thickness of the pressure-sensitive adhesive layer (Z) is not particularly limited, but from the viewpoint of improving the handleability when using the film for latex ink as a pressure-sensitive adhesive film, it is preferably 5 μm to 100 μm, more preferably 10 μm to 70 μm, and even more preferably 15 μm to 50 μm.

[0077] <Release Liner> The film for latex ink of one embodiment of the present invention may have a release liner together with the pressure-sensitive adhesive layer (Z). By covering the adhesive surface of the pressure-sensitive adhesive layer (Z) of the film for latex ink of one embodiment of the present invention with a release liner, the adhesive surface of the pressure-sensitive adhesive layer (Z) can be suitably protected during transportation and storage of the film for latex ink.

[0078] The release liner is not particularly limited, and release liners commonly used in the field of adhesive films can be used as appropriate. Examples of release liners include laminates in which a release layer is provided on the surface of a film substrate or a paper substrate. Examples of film substrates include polyester resins such as polyethylene terephthalate, and polyolefin resins such as polyethylene resins and polypropylene resins. Examples of paper substrates include papers such as fine paper, kraft paper, and glassine paper. Examples of materials constituting the release layer include silicone, long-chain alkyl resins, and fluorine-based resins.

[0079] The thickness of the release liner is not particularly limited, but is preferably 10 μm to 150 μm, more preferably 20 μm to 130 μm, and even more preferably 30 μm to 100 μm.

[0080] [Method for Producing Film for Latex Ink] The method for producing the film for latex ink of the present invention is not particularly limited, and may be appropriately selected depending on the configuration of the film for latex ink.

[0081] <Method of Forming Latex Ink Receiving Layer (X)> A preferred method of forming the latex ink receiving layer (X) is to apply the resin composition (x1) to one surface (Ya) of the substrate (Y) to form a coating film, dry the coating film, and then UV-cure and crosslink the coating to form the latex ink receiving layer (X). In order to improve the workability of application to the substrate (Y), the resin composition (x1) is preferably further diluted with a dilution solvent to form a solution.

[0082] Examples of the dilution solvent include organic solvents such as methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexane, n-hexane, toluene, xylene, n-propanol, and isopropanol. The concentration of the active ingredient in the solution of the resin composition (x1) is preferably 10 to 50% by mass.

[0083] Examples of the method for applying the solution of the resin composition (x1) include Mayer bar coating, gravure coating, roll coating, knife coating, and die coating.

[0084] The resin composition (x1) is applied to one surface (Ya) of the substrate (Y) to form a coating film, and then the coating film is dried to remove the dilution solvent from the coating film (drying step). Heating conditions for drying the coating film include, for example, a drying temperature of 60°C to 120°C and a drying time of 30 seconds to 3 minutes.

[0085] After drying the coating film, the coating film is irradiated with ultraviolet light to cure (polymerize) the ultraviolet-curable acrylate compound (C) (ultraviolet light irradiation step). The ultraviolet light irradiation conditions are an integrated irradiation amount (integrated light amount) of 5 to 1200 mJ / cm. 2 is preferred, and 50 to 500 mJ / cm 2 The ultraviolet light can be irradiated using, for example, a high-pressure mercury lamp, an electrodeless UV lamp, a xenon lamp, an LED, or the like as an ultraviolet light source.

[0086] After curing (polymerizing) the ultraviolet-curable acrylate compound (C), the acrylic resin (A) having a crosslinkable functional group is reacted with the crosslinking agent (B) to form a crosslinked structure (crosslinking step). The crosslinking conditions are not particularly limited, and for example, the crosslinking may be carried out by leaving the mixture in a normal environment (e.g., 23°C, relative humidity 50°C) for 1 day to 14 days or less, or by leaving the mixture in an environment of 40°C to 60°C for 1 day to 3 days.

[0087] The ultraviolet irradiation step may be performed before, during, or after the crosslinking step. The crosslinking step and the ultraviolet irradiation step may be performed simultaneously, or the crosslinking step and the ultraviolet irradiation step may each be performed multiple times. Furthermore, at least one of the ultraviolet irradiation step and the crosslinking step may be performed simultaneously with the drying step.

[0088] <Method of Forming Pressure-Sensitive Adhesive Layer (Z)> When the film for latex ink of one embodiment of the present invention has a pressure-sensitive adhesive layer (Z), the pressure-sensitive adhesive layer (Z) is formed on the other surface (Yb) of the substrate (Y) on which the latex ink-receiving layer (X) is not formed. The pressure-sensitive adhesive layer (Z) is formed, for example, by applying a composition for forming the pressure-sensitive adhesive layer (pressure-sensitive adhesive layer-forming composition) to the other surface (Yb) of the substrate (Y). Alternatively, the pressure-sensitive adhesive layer (Z) may be formed by applying the pressure-sensitive adhesive layer-forming composition to the release surface of a release liner, and then the pressure-sensitive adhesive layer (Z) may be laminated (transferred) to the other surface (Yb) of the substrate (Y). The method of applying the pressure-sensitive adhesive layer-forming composition is the same as that described above for the resin composition (x1).

[0089] [Uses of Latex Ink Film, etc.] The latex ink film of the present invention is preferably used for printing using latex ink. Therefore, according to the present invention, there is provided a method of using the latex ink film to form a printed section on the latex ink-receiving layer of the latex ink film using latex ink. Also, according to the present invention, there is provided a method for producing a printed item, which includes a step of forming a printed section on the latex ink-receiving layer of the latex ink film using latex ink. Furthermore, according to the present invention, there is provided a printed item having a printed section printed with latex ink on the latex ink-receiving layer of the latex ink film.

[0090] Below, we will explain the latex ink used to form a printed area on the latex ink-receiving layer of the latex ink film of the present invention, and then we will explain the method for forming a printed area on the latex ink-receiving layer of the latex ink film of the present invention.

[0091] <Latex Ink> Latex ink contains a liquid dispersion medium and a dispersoid composed of a material containing at least a resin, dispersed (emulsified and / or suspended) in the dispersion medium. Latex ink has a low environmental impact. Another advantage of latex ink is that it can produce deep colors with a thin layer. The latex particles that make up latex ink contain a binder (resin), which is generally advantageous in improving the adhesion of the pigment colorant to the recording medium. Another advantage is that it can be printed on demand using an inkjet method. It is also preferable that the latex ink is a water-based ink. Water-based inks are safer and have a lower environmental impact because they suppress the generation of volatile organic compounds caused by organic solvents.

[0092] (Resin) The resin contained in the latex ink is not particularly limited, but examples include vinyl resins, acrylic resins, styrene resins, alkyd resins, polyester resins, polyurethane resins, silicone resins, fluorine-based resins, epoxy resins, phenoxy resins, polyolefin resins, and modified resins thereof (e.g., modified resins modified to be water-soluble). One or more selected from these may be used in combination. Among these, acrylic resins, styrene resins, water-soluble polyurethane resins, water-soluble polyester resins, and water-soluble acrylic resins are preferred, with acrylic resins being more preferred. The latex ink used in the latex ink film of one embodiment of the present invention is preferably a latex ink containing an acrylic resin, from the viewpoint of further improving adhesion between the latex ink-receiving layer (X) and the printed area. The resin content in the latex ink is preferably 1% by mass to 20% by mass, more preferably 2% by mass to 10% by mass, based on the total amount of the latex ink.

[0093] (Dispersion Medium) The latex ink contains water as a dispersion medium. The content of the dispersion medium (water) in the latex ink is preferably 50% by mass to 98% by mass, more preferably 60% by mass to 97% by mass, and even more preferably 70% by mass to 96% by mass, based on the total mass of the latex ink.

[0094] (Colorant) Latex inks usually contain a colorant. Various dyes, pigments, etc. can be used as the colorant. The content of the colorant in the latex ink is preferably 0.1% by mass to 20% by mass, and more preferably 0.2% by mass to 10% by mass, based on the total mass of the latex ink.

[0095] (Other Components) The latex ink may contain components other than those described above (other components), such as dispersants, antifungals, antirust agents, pH adjusters, surfactants, plasticizers, UV absorbers, and light stabilizers.

[0096] <Formation of Printed Section> The printed section using latex ink is formed by applying the latex ink onto the latex ink-receiving layer (X) of the latex ink film. The latex ink is preferably a latex ink containing an acrylic resin, from the viewpoint of further improving adhesion between the latex ink-receiving layer (X) and the printed section. The method for applying the latex ink is not particularly limited, and various printing methods can be used, but inkjet printing is preferred. Examples of inkjet printing methods include piezo printing and thermal jet printing. The film for latex ink may be heated when applying the latex ink. The heating temperature is not particularly limited, but is preferably 40°C to 90°C. This method results in a printed matter having a printed section using latex ink on the latex ink-receiving layer (X) of the latex ink film. The latex ink is preferably a latex ink containing an acrylic resin, from the viewpoint of further improving adhesion between the latex ink-receiving layer (X) and the printed section.

[0097] The present invention will be specifically described with reference to the following examples, but the present invention is not limited to these examples.

[0098] [Methods for measuring various physical properties] The methods for measuring various physical properties in the present examples are as follows. (1) Hydroxyl value The hydroxyl value of the acrylic resin (A) having a crosslinkable functional group was measured in accordance with JIS K0070:1992. (2) Acid value The acid value of the acrylic resin (A) having a crosslinkable functional group was measured in accordance with JIS K0070:1992. (3) Glass transition temperature (Tg) The glass transition temperature (Tg) of the acrylic resin (A) having a crosslinkable functional group was measured in accordance with JIS K 7121:2012 using a differential scanning calorimeter (manufactured by TA Instruments Japan, product name "DSC Q2000") at a heating rate of 20°C / min. (4) Thickness of Each Layer The thickness of each layer was measured using a constant pressure thickness measuring instrument manufactured by Teclock Corporation (model number: "PG-02J", standard specifications: JIS K6783: 1994, JIS Z1702: 1994, JIS Z1709: 1995).

[0099] [Examples 1 to 4, Comparative Example 1] Inkjet printing sheets provided with latex ink films of Examples 1 to 4 and Comparative Example 1 were prepared by the following procedure.

[0100] <Preparation of Resin Composition> To prepare the resin composition, an acrylic resin (A) having a crosslinkable functional group, a crosslinking agent (B), an ultraviolet-curable acrylate compound (C), and a photopolymerization initiator (D) shown below were used.

[0101] (Acrylic Resin (A) Having Crosslinkable Functional Group) An acrylic resin having a crosslinkable functional group, which has a hydroxyl value of 11.0 mgKOH / g, an acid value of 3.9 mgKOH / g, and a glass transition temperature (Tg) of 90°C, was used.

[0102] (Crosslinking Agent (B)) A partially modified product of an isocyanurate compound (an isocyanurate compound (B1) containing an isocyanurate compound (B1-1) and a modified product of an isocyanurate compound (B1-2)) was used.

[0103] (UV-Curable Acrylate Compounds (C)) - "Hexafunctional (Alkylene Oxide Modified)": Ethylene oxide-modified dipentaerythritol hexaacrylate (ethoxylated dipentaerythritol hexaacrylate) was used. The ethylene oxide-modified dipentaerythritol hexaacrylate is an ester of a polyol compound (ethylene oxide mole number: 12) that is an ethylene oxide-modified product of dipentaerythritol with acrylic acid, and is a complete ester having six acryloyl groups. - "Tetrafunctional (Alkylene Oxide Modified)": Ethylene oxide-modified pentaerythritol tetraacrylate (ethoxylated pentaerythritol tetraacrylate) was used. The ethylene oxide-modified pentaerythritol tetraacrylate is an ester of a polyol compound (ethylene oxide mole number: 4) that is an ethylene oxide-modified product of pentaerythritol with acrylic acid, and is a complete ester having four acryloyl groups.

[0104] (UV-Curable Acrylate Compound (C')) "Tetrafunctional (Unmodified with Alkylene Oxide)": Pentaerythritol tetraacrylate was used. The pentaerythritol tetraacrylate is an ester of pentaerythritol and acrylic acid, and is a complete ester having four acryloyl groups.

[0105] (Photopolymerization initiator (D)) 1-hydroxycyclohexyl phenyl ketone was used.

[0106] (Other additives) Tin-based catalysts

[0107] As the substrate (Y), a polyethylene terephthalate sheet (thickness: 50 μm) with an easy-adhesion layer was prepared. Then, a coating liquid (active ingredient concentration: 10 mass%, diluent: ethyl acetate) of a resin composition prepared by adjusting the formulation (amount of active ingredient) shown in Table 1, which contains an acrylic resin (A) having a crosslinkable functional group, a crosslinking agent (B), an ultraviolet-curable acrylate compound (C) (or an ultraviolet-curable acrylate compound (C')), and a tin-based catalyst, was applied to the easy-adhesion layer side of the substrate (Y) using a Meyer bar so that the film thickness after drying was 1 μm. Next, by heating under conditions of 90 ° C. and 1 minute using a hot air dryer, the diluent solvent contained in the coating film formed by coating the substrate (Y) was removed (drying process), and then ultraviolet light having a peak wavelength at a wavelength of 365 nm was applied to the substrate (Y) at an integrated light intensity of 150 mJ / cm ２ The film was then irradiated with ultraviolet light (ultraviolet curing step), and further left to stand for 7 days in an environment of 23°C and 50% relative humidity to allow crosslinking (crosslinking step). This formed a latex ink-receiving layer (X) with a thickness of 1 μm, and films for latex inks of Examples 1 to 4 and Comparative Example 1 were obtained. Next, an acrylic pressure-sensitive adhesive composition was applied to the release agent side of the release liner so that the film would have a dry thickness of 20 μm, and the film was heated at 90°C for 1 minute using a hot air dryer to remove the solvent contained in the acrylic pressure-sensitive adhesive composition, thereby forming an acrylic pressure-sensitive adhesive layer. The acrylic pressure-sensitive adhesive layer formed on the release liner was then bonded to the surface of the substrate (Y) opposite the surface from which the latex ink-receiving layer (X) was formed, and inkjet printing sheets comprising the films for latex inks of Examples 1 to 4 and Comparative Example 1 were obtained.

[0108] <Evaluation 1> (1) Evaluation of Ink Adhesion (Dry) For each of the inkjet printing sheets including the latex ink film of Examples 1 to 4 and Comparative Example 1, a predetermined test pattern was printed on the surface of the latex ink-receiving layer (X) by an inkjet method using a latex ink (HP882, manufactured by Hewlett-Packard) with an inkjet printer (HP Latex R2000, manufactured by Hewlett-Packard). The inkjet printing sheets with the predetermined test pattern printed on the surface of the latex ink-receiving layer (X) were then left to stand for one day in an environment of 23°C and 50% relative humidity to prepare test samples. A 100 mm x 24 mm piece of Nichiban Cellotape (registered trademark) was then attached to the side of the test sample on which the printed portion was formed. The remaining area (remaining area / total area) of the printed portion after the tape was removed was determined and evaluated according to the following criteria. 1: Residual rate less than 20% 2: Residual rate 20% or more and less than 40% 3: Residual rate 40% or more and less than 60% 4: Residual rate 60% or more and less than 90% 5: Residual rate 90% or more The higher the residual rate, the better the ink adhesion of the latex ink-receiving layer (X). In this example, a rating of 4 or more was considered to be acceptable.

[0109] (2) Evaluation of Water-Resistant Ink Adhesion For each of the inkjet printing sheets provided with the latex ink films of Examples 1 to 4 and Comparative Example 1, a predetermined test pattern was printed to form a printed portion (printed layer) in the same manner as in "(1) Evaluation of Ink Adhesion (Dry)." Then, the inkjet printing sheets with the predetermined test pattern printed on the surface of the latex ink-receiving layer (X) were left to stand for one day in an environment of 23°C and 50% relative humidity to prepare test samples. A 3% by mass aqueous solution of an anionic surfactant (sodium laureth sulfate) was then sprayed onto the entire surface of the test sample on which the printed portion was formed, and the test sample was then left to stand for 10 minutes. The entire surface on which the printed portion was formed was then vigorously rubbed with a rubber squeegee to determine the remaining area of ​​the printed portion (remaining area / total area), and the result was evaluated according to the following criteria. 1: Residual rate less than 20% 2: Residual rate 20% or more and less than 40% 3: Residual rate 40% or more and less than 60% 4: Residual rate 60% or more and less than 90% 5: Residual rate 90% or more The higher the residual rate of the printed portion, the better the water-resistant adhesion of the ink of the latex ink-receiving layer (X). In this example, a rating of 4 or more was considered to be acceptable.

[0110] (3) Evaluation of Scratch Resistance For each of the inkjet printing sheets provided with the latex ink film of Examples 1 to 4 and Comparative Example 1, the surface (unprinted) of the latex ink receiving layer (X) was scratched with #0000 steel wool at a rate of 250 g / cm ２ After rubbing 10 times with a load, the degree of damage was checked and evaluated according to the following criteria: S: No damage; A: Only slight damage; B: Damage was observed, but the product was usable; C: Many scratches occurred. In this example, a rating of B or higher was considered to be acceptable.

[0111] The results are shown in Table 1.

[0112]

[0113] Table 1 reveals the following: The films for latex inks of Examples 1 to 4 are excellent in ink adhesion and water-resistant ink adhesion while ensuring abrasion resistance. On the other hand, the film for latex inks formed from the resin composition (x1) in which the UV-curable acrylate compound (C'), which is an ester of acrylic acid and a non-alkylene oxide-modified polyol compound, was blended in place of the UV-curable acrylate compound (C), as in Comparative Example 1, is found to have insufficient water-resistant ink adhesion.

[0114] 1: film for latex ink; X: latex ink receiving layer; Y: substrate; Ya: one surface of substrate; Yb: other surface of substrate; Z: adhesive layer

Claims

1. a laminated structure in which a latex ink-receiving layer (X) and a substrate (Y) are laminated, the latex ink-receiving layer (X) is formed from a resin composition (x1) containing an acrylic resin (A) having a crosslinkable functional group, a crosslinking agent (B), an ultraviolet-curable acrylate compound (C) which is an ester of an alkylene oxide-modified polyol compound and (meth)acrylic acid, and a photopolymerization initiator (D); The crosslinking agent (B) contains an isocyanurate compound (B1), The isocyanurate compound (B1) includes an isocyanurate compound (B1-1) and a modified isocyanurate compound (B1-2), The isocyanurate compound (B1-1) is a trimer of 1,6-hexamethylene diisocyanate, The modified isocyanurate compound (B1-2) is a trimer of 1,6-hexamethylene diisocyanate and has one or more tertiary amino groups.

2. The film for latex ink according to claim 1 , wherein the substrate (Y) comprises a polyester-based resin.

3. the latex ink-receiving layer (X) is laminated on one surface of the substrate (Y), The film for latex ink according to claim 1 or 2, further comprising a pressure-sensitive adhesive layer (Z) provided on the other surface of the substrate (Y).

4. 4. The film for latex ink according to claim 3, wherein the adhesive surface of the adhesive layer (Z) is covered with a release liner.

5. 3. The film for latex ink according to claim 1, which is used for printing using a latex ink containing an acrylic resin.

6. A method for using the film for latex ink according to claim 1 or 2 to form a printed portion on the latex ink-receiving layer of the film for latex ink using latex ink.

7. A method for producing a printed matter, comprising the step of forming a printed portion on the latex ink-receiving layer of the film for latex ink according to claim 1 or 2 using latex ink.

8. A printed matter having a printed area printed with latex ink on the latex ink-receiving layer of the film for latex ink according to claim 1 or 2.