JP6909753B2 - Printed matter - Google Patents

Description

The present invention relates to a printed matter obtained by laminating an ink layer made of active energy ray-curable ink on the surface of an ink receiving layer.

Conventionally, a printing method using an inkjet printer has been used to decorate a base material such as plastic or a building board. In decoration with an inkjet printer, it is common that an ink receiving layer is provided on the base material and printing is performed on the ink receiving layer, instead of printing the ink directly on the base material. In recent years, attention has been paid to active energy ray-curable inks having a short curing time and excellent productivity, and printing systems using active energy ray-curable inks have been developed.

The ink receiving layer to which the active energy ray-curable ink is applied is disclosed in, for example, Patent Documents 1 and 2. More specifically, Patent Document 1 discloses a coating material for a receiving layer, which is an acrylic resin emulsion having a calculated glass transition point Tg of 35 to 90 ° C. Further, Patent Document 2 discloses an emulsion coating material of a thermoplastic resin containing a cross-linking agent as a coating material for a receiving layer.

Further, such a base material such as a building board or a colored board may be accompanied by a peculiar odor in a period shortly after production, and it is required to reduce the odor of ink or printed matter. In particular, reducing the amount of monomer emitted from the ink used has been an issue. Patent Document 3 discloses an ink in which the monomer odor is reduced by adjusting the contents of the monomer and the photopolymerization initiator contained in the ink. Patent Document 4 discloses that a monomer odor is suppressed by providing an ozone generating means in the ink coating unit.

Japanese Unexamined Patent Publication No. 2010-112073 Japanese Unexamined Patent Publication No. 2013-63570 Japanese Unexamined Patent Publication No. 2005-154537 Japanese Unexamined Patent Publication No. 2010-208042

When printing with active energy ray-curable ink is performed on the receiving layer obtained from the conventional coating for the receiving layer, the monomer in the active energy ray-curable ink remains in the receiving layer in an uncured state. , Unreacted monomer may be emitted from the decorated product provided with the receiving layer.

Further, when printing is performed using the active energy ray-curable ink, the dots are difficult to spread on the conventional receiving layer, and the color development of the image is difficult to be improved. On the other hand, there is also a method of forming a dense receiving layer so that the monomer in the active energy ray-curable ink does not penetrate into the receiving layer, but in this case, it is difficult to obtain the adhesive force due to the anchor effect.

Further, from the viewpoint of active energy ray-curable ink, there is a method of adjusting the content of the monomer and the photopolymerization initiator as a method of reducing the amount of unreacted monomer after the ink is cured. Not enough to reduce the remaining unreacted monomers. Further, although there is a method of using a monomer having a low odor, it may be difficult to sufficiently satisfy the film characteristics such as weather resistance and color development of the ink film because the design width of the ink cannot be sufficiently obtained. Further, a method of providing an ozone generating means in the ink coating unit is also disclosed, but there is a concern that it may lead to an increase in the cost of manufacturing equipment.

The present invention has been made in view of the above problems, and even when a receiving layer in which the monomer in the active energy ray-curable ink does not easily permeates is used, the active energy ray-curable ink and the receiving layer are used. It is an object of the present invention to provide a printed matter having excellent adhesiveness and a small amount of unreacted monomer emitted from the printed matter.

The present inventors have found that the object of the present invention is achieved by the following.

(1) An ink receiving layer having an ink absorption rate of 100% or less is laminated on the surface of a base material, and an ink layer made of an active energy ray-curable ink containing a polymerizable compound is laminated on the surface of the ink receiving layer. A printed matter having a glass transition temperature of the polymerizable compound of 45 to 25 ° C.
(2) The above-mentioned 1 above, wherein the ink receiving layer contains a polymer containing 25 to 85% by mass of at least one structural unit derived from an ethylenically unsaturated monomer having a solubility parameter of 9.50 to 13.0. Printed matter.
(3) The printed matter according to 1 or 2 above, wherein the elongation rate of the ink receiving layer is 10 to 30%.
(4) The printed matter according to any one of 1 to 3 above, wherein the proportion of the monofunctional monomer contained in the polymerizable compound is 50% by mass or more.

According to the present invention, even when a receiving layer in which the monomer in the active energy ray-curable ink does not easily penetrate is used, the adhesiveness between the active energy ray-curable ink and the receiving layer is excellent, and the printed matter is unreacted. It is possible to provide a printed matter in which the amount of monomer emitted is small.

Hereinafter, embodiments of the present invention will be described in detail.
<Printed matter>
In the printed matter of the present invention, an ink receiving layer having an ink absorption rate of 100% or less is laminated on the surface of a base material, and an ink layer made of an active energy ray-curable ink containing a polymerizable compound is laminated on the surface of the ink receiving layer. The printed matter is characterized in that the glass transition temperature of the polymerizable compound is 45 to 25 ° C.

≪Ink receiving layer≫
The ink receiving layer of the present invention can be formed by applying a coating material for an ink receiving layer on the surface of a base material and curing the ink receiving layer.
The coating material for an ink receiving layer of the present invention contains an aqueous dispersion of resin particles containing a resin, and in this resin, the ratio of structural units derived from a monomer having a cyclic structure exceeds 0 and is 28% by mass or less. It is preferably used.

The resin is not particularly limited, and for example, a polymer containing a structural unit derived from a monomer having no cyclic structure, a polymer containing a structural unit derived from a monomer having no cyclic structure, and a structural unit derived from a monomer having a cyclic structure. Can be mentioned. Each of the structural unit derived from the monomer having no cyclic structure and the structural unit derived from the monomer having a cyclic structure may be used alone or in combination of two or more.

Examples of the monomer having a cyclic structure include an alicyclic group-containing unsaturated hydrocarbon, an aromatic ring-containing unsaturated hydrocarbon, an alicyclic group-containing unsaturated carboxylic acid, an alicyclic group-containing unsaturated carboxylic acid ester, and a fat. Aromatic group-containing unsaturated carboxylic acid amide, aromatic ring-containing unsaturated carboxylic acid, aromatic ring-containing unsaturated carboxylic acid ester, aromatic ring-containing unsaturated carboxylic acid amide, alicyclic group-containing alkoxysilane, aromatic ring-containing alkoxysilane, etc. Can be mentioned. The alicyclic group and the aromatic ring may have a hetero atom such as a nitrogen atom or an oxygen atom in the ring, or may have a substituent.

The alicyclic group is not particularly limited, and is, for example, an alicyclic hydrocarbon group such as a cycloalkyl group (for example, a cyclohexyl group) or a cycloalkenyl group (for example, a cyclohexenyl group); an alicyclic group such as a piperidyl group. The formula heterocyclic group can be mentioned. The aromatic ring is not particularly limited, and examples thereof include an aromatic carbocycle such as a benzene ring, a naphthalene ring, and an anthracene ring; and an aromatic heterocycle such as a pyridine ring.

Specific examples of the alicyclic group-containing unsaturated hydrocarbon include vinylcyclohexane and the like. Specific examples of the aromatic ring-containing unsaturated hydrocarbon include styrene and the like. Specific examples of the alicyclic group-containing unsaturated carboxylic acid include 3-cyclohexylacrylic acid. Specific examples of the alicyclic group-containing unsaturated carboxylic acid ester include cyclohexyl (meth) acrylate, glycidyl methacrylate, 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate and the like.

Specific examples of the alicyclic group-containing unsaturated carboxylic acid amide include N-cyclohexyl (meth) acrylamide and the like. Specific examples of the aromatic ring-containing unsaturated carboxylic acid include 3-phenyl (meth) acrylic acid. Specific examples of the aromatic ring-containing unsaturated carboxylic acid ester include phenyl (meth) acrylate and the like. Specific examples of the aromatic ring-containing unsaturated carboxylic acid amide include N-phenyl (meth) acrylamide and the like. Specific examples of the alicyclic group-containing alkoxysilane include 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropyltriethoxysilane.

Specific examples of the aromatic ring-containing alkoxysilane include 3-phenoxypropyltrimethoxysilane and 3-phenoxypropyltriethoxysilane. From the viewpoint of color development of the ink receiving layer, cyclohexyl methacrylate, styrene, glycidyl methacrylate, 3-glycidoxypropyltriethoxysilane, 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate and the like are preferable.

The monomer having no cyclic structure is not particularly limited, and is, for example, a linear or branched unsaturated hydrocarbon, a linear or branched unsaturated carboxylic acid, or a linear or branched unsaturated carboxylic acid. Examples thereof include acid esters, linear or branched unsaturated carboxylic acid amides, and the like. Specific examples of linear or branched unsaturated hydrocarbons include ethylene and propylene. Specific examples of the linear or branched unsaturated carboxylic acid include (meth) acrylic acid and the like.

Specific examples of the linear or branched unsaturated carboxylic acid ester include alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate. Alkenyl (meth) acrylates such as allyl (meth) acrylates; 3- (meth) acryloyloxypropyltrialkoxysilanes such as 3- (meth) acryloyloxypropyltrimethoxysilane and 3- (meth) acryloyloxypropyltriethoxysilane. And so on. Specific examples of the linear or branched unsaturated carboxylic acid amide include diacetone (meth) acrylamide and the like.

As the monomer having no cyclic structure, methyl methacrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, butyl methacrylate, methacrylic acid, diacetone acrylamide, 3-methacryloyloxypropyltrimethoxysilane, and allyl methacrylate are preferable.

In the present specification, (meth) acrylic acid means acrylic acid or methacrylic acid, (meth) acrylate means acrylate or methacrylate, and (meth) acrylamide means acrylamide or methacrylamide. means.

In the above resin, the ratio of the structural unit derived from the monomer having a cyclic structure is more than 0 and 28% by mass or less, preferably 0.01 to 26% by mass, and more preferably 0.1 to 25% by mass. The slight presence of the monomer having a cyclic structure can be expected to be effective in adjusting the dot diameter.

The resin is a polymer containing at least one structural unit derived from an ethylenically unsaturated monomer having a solubility parameter of 9.50 to 13.0, preferably 25 to 85% by mass.
In the present specification, the ethylenically unsaturated monomer means a monomer having a double bond in the molecule and causing a polymerization reaction through addition to the double bond. The ethylenically unsaturated monomer is not particularly limited, and examples thereof include a monomer having no cyclic structure and a monomer having a cyclic structure, among those exemplified above, having the above-mentioned double bond.

The calculated glass transition temperature of the resin is preferably -15 to 85 ° C., more preferably -10 to 50 ° C., and even more preferably -5 to 40 ° C. from the viewpoint of reducing unreacted monomers. be. When the calculated glass transition temperature is −15 ° C. or higher, a sticky feeling is unlikely to remain after drying.
When the calculated glass transition temperature is 85 ° C. or lower, drying is unlikely to be delayed. In the present specification, the calculated glass transition temperature means the glass transition temperature calculated by the Fox formula.

The method for producing an aqueous dispersion of resin particles containing the resin is, for example, according to a conventional method, having a monomer having no cyclic structure, a monomer having no cyclic structure, and a cyclic structure in an aqueous medium containing water as a main component. It can be produced by subjecting it to a combination with a monomer or the like for emulsion polymerization.

The content of the resin is preferably 10 to 60% by mass, more preferably 20 to 45% by mass, based on the components forming the ink receiving layer. When the content is 10 to 60% by mass, the monomer is unlikely to remain after the printing, and the ink receiving layer and the ink layer or the ink receiving layer and the clear layer while maintaining the performance excellent in color development. Adhesion can be enhanced.

The paint for the ink receiving layer according to the present invention may contain a pigment in addition to the above-mentioned aqueous dispersion. The pigment is not particularly limited, and examples thereof include a coloring pigment (for example, a white pigment), a rust preventive pigment, and an extender pigment generally used in the coating industry.

Specific examples of coloring pigments, rust preventive pigments, and extender pigments include titanium oxide, red iron oxide, yellow iron oxide, carbon black, aluminum tripolyphosphate, zinc phosphate, condensed aluminum phosphate, barium metaborate, calcium carbonate, and sulfuric acid. Inorganic pigments such as barium, kaolin, talc, clay, mica, alumina, myoban, white clay, magnesium hydroxide, and magnesium oxide, phthalocyanine blue, phthalocyanine green, naphthol red, quinacridone red, benzimidazolone yellow, Hansa yellow, benz Examples thereof include organic pigments such as imidazolone orange and dioxazine violet. The pigment may be used alone or in combination of two or more.

The content of the pigment is preferably 35 to 85% by mass, more preferably 40 to 75% by mass, based on the components forming the ink receiving layer. When the content is 35 to 85% by mass, the monomer is unlikely to remain after the printing, and the ink receiving layer and the ink layer or the ink receiving layer and the clear layer while maintaining the performance excellent in color development. Adhesion can be enhanced.

The paint for the ink receiving layer according to the present invention may further contain a film forming aid. From the viewpoint of film forming property, the content of the film forming aid is preferably 0 to 10% by mass with respect to the above coating material.

In addition to the above-mentioned components, the ink receiving layer coating material according to the present invention includes additives commonly used in the coating industry, such as photopolymerization initiators, light stabilizers, polymerization inhibitors, organic solvents, and antioxidants. , Silane coupling agent, plasticizer, defoaming agent, surface conditioner, wet dispersant, rheology control agent, ultraviolet absorber, viscosity adjuster, preservative, etc. are appropriately selected within a range that does not impair the object of the present invention. May be blended.

The ink absorption rate of the coating film made of the dried product of the ink receiving layer coating material according to the present invention is 100% or less, preferably 90% or less, and more preferably 85% or less. When the ink absorption rate is 100% or less, the amount of the monomer in the active energy ray-curable ink remaining in the receiving layer in an uncured state can be reduced, and the decorated product provided with the receiving layer has an odor. Can be effectively suppressed. In addition, in this specification, an ink absorption rate means an amount measured by the method described in an Example.

Further, the toughness of the coating film tends to be obtained by adjusting the elongation rate of the coating film made of the dried product of the ink receiving layer coating material according to the present invention to 10% or more. The elongation rate of the coating film can be adjusted by adjusting the intermolecular crosslink density of the resin and the content of the pigment, which will be described later.

In the resin particles in the ink receiving layer coating material according to the present invention, it is preferable that crosslinks are present between the molecules of the resin. When crosslinks are present between the molecules of the resin, (1) the higher the crosslink density, the more the permeation of the active energy ray-curable ink into the ink receiving layer is suppressed, so that the monomer in the ink is accepted in an uncured state. It is easy to reduce the amount remaining in the layer, and it is possible to effectively suppress the generation of odor from the decorated product provided with the receiving layer, and (2) the ink receiving layer for the above-mentioned monomer and solvent. Dissolution resistance is likely to improve.

Cross-linking between the molecules of the resin can be performed by using a cross-linking monomer as a raw material monomer for producing the resin, for example, 3-methacryloyloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, glycidylmethacrylate, allyl. It can be introduced by using methacrylate or the like in combination. For example, epoxy groups react with carboxyl groups such as acrylic acid and methacrylic acid. The crosslinkable monomer used for introducing the crosslink between the molecules of the resin may be used alone or in combination of two or more.

In the ink receiving layer coating material according to the present invention, it is preferable that crosslinks are present between the particles. When crosslinks are present between the particles, the higher the crosslink density, the more the permeation of the active energy ray-curable ink into the ink receiving layer is suppressed, so that the monomers in the ink remain in the receiving layer in an uncured state. It is easy to reduce the amount, and it is possible to effectively suppress the generation of odor from the decorated product provided with the receiving layer.
Crosslinking between the particles can be introduced by using a crosslinkable monomer such as diacetone acrylamide and N- (butoxymethyl) acrylamide in combination as a raw material monomer for producing the resin.

Examples of the cross-linking between the particles include those introduced via a cross-linking agent such as a compound having an oxazoline group and adipic acid dihydrazide, and those introduced by self-cross-linking the resins between the particles. When a compound having an oxazoline group is used, the carboxyl group in the resin is involved in the cross-linking reaction. When adipic acid dihydrazide is used, the carbonyl group in the resin is involved in the cross-linking reaction.

When N- (butoxymethyl) acrylamide is contained in the raw material monomer, the butoxy group is eliminated by heating to generate a methylol group, and then the resins existing on different particles are self-crosslinked. Each of the cross-linking monomer and the cross-linking agent used for introducing the cross-linking between the particles may be used alone or in combination of two or more.

≪Active energy ray-curable ink≫
The active energy ray-curable ink of the present invention contains a coloring pigment. Known materials can be used as the coloring pigment, for example, carbon black, yellow iron oxide, petals, composite oxides (nickel / titanium type, chromium / titanium type, bismuth / vanadium type, cobalt / aluminum type, cobalt / titanium type). Inorganic pigments such as aluminum / chromium type, ultramarine blue), titanium oxide, quinacridone type, diketopyrrolopyrrole type, benzimidazolone type, isoindolinone type, anthrapyrimidine type, phthalocyanine type, slene type, dioxazine type, Examples include azo-based organic pigments. From the viewpoint of weather resistance, it is preferable to use an inorganic pigment.

The content of the coloring pigment in the ink is not particularly limited. The content is preferably 2 to 20% by mass from the viewpoint of color development of the ink.

The ink preferably contains a dispersant. As the dispersant, an anionic dispersant, a cationic dispersant and a nonionic dispersant are preferable. As the dispersant, a commercially available product can be preferably used.

≪Polymerizable compound≫
The active energy ray-curable ink of the present invention contains a polymerizable compound such as an active energy ray-polymerizable monomer. The active energy ray-polymerizable monomer is a monomer that undergoes a polymerization reaction when irradiated with an active energy ray such as ultraviolet rays. For example, as a functional group exhibiting reactivity when irradiated with an active energy ray, a vinyl group, an acryloyloxy group, or a methacryloyloxy group is used. Those having a group are preferable.
The cured product obtained after the polymerization of a polymerizable compound such as an active energy ray-polymerizable monomer functions as a binder.

The polymerizable compound of the present invention is characterized by having a glass transition temperature (hereinafter, sometimes abbreviated as Tg) of 45 to 25 ° C. By using this Tg polymerizable compound, an ink layer having excellent adhesion to the receiving layer is formed even when a receiving layer in which the monomer contained in the active energy ray-curable ink does not easily penetrate is used. be able to.
The Tg of the polymerizable compound referred to here can be determined by the following FOX formula.
1 / Tg = W1 / Tg1 + W2 / Tg2 + ... + Wn / Tgn
In the formula, Tg is the calculated Tg (° K), W1, W2, ..., Wn is the mass fraction of each monomer, and Tg1, Tg2, ..., Tgn is the homomer of each monomer. The glass transition temperature (° K) of the polymer.
As the active energy ray-polymerizable monomer, a monofunctional monomer having 1 functional group, a bifunctional monomer having 2 functional groups, and a polyfunctional monomer having 3 or more functional groups can be used.

Among the above active energy ray-polymerizable monomers, the monofunctional monomer preferably has a molecular weight of 1000 or less, and specific examples thereof include stearyl acrylate, acryloyl morpholine, tridecyl acrylate, lauryl acrylate, N, N-dimethylacrylamide. , Decyl acrylate, 2-phenoxyethyl acrylate, isodecyl acrylate, isobornyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, isooctyl acrylate, octyl acrylate, dicyclopentenyloxyethyl acrylate, cyclohexyl acrylate, N-vinyl Caprolactam, isoamyl acrylate, 2-ethylhexyl-diglycol acrylate, EO (ethylene oxide) modified 2-ethylhexyl acrylate, neopentyl glycol acrylate benzoic acid ester, N-vinyl-2-pyrrolidone, N-vinylimidazole, tetrahydrofurfuryl acrylate, Examples thereof include methoxydipropylene glycol acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl) methyl acrylate, cyclic trimethylolpropaneformal acrylate, ethoxy-diethylene glycol acrylate, 4-hydroxybutyl acrylate and the like. .. These monofunctional monomers may be used alone or in combination of two or more.

Among the above active energy ray-polymerizable monomers, the bifunctional monomer preferably has a molecular weight of 1000 or less, and specific examples thereof include 1,10-decanediol diacrylate and 2-methyl-1,8-octanediol. Diacrylate, 2-butyl-2-ethyl-1,3-propanediol diacrylate, 1,9-nonanediol diacrylate, 1,8-octanediol diacrylate, 1,7-heptanediol diacrylate, polytetramethylene Glycol diacrylate, 3-methyl-1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, neopentyl glycol diacrylate hydroxypivalate, tripropylene glycol diacrylate, 1,4 -Butanediol diacrylate, dipropylene glycol diacrylate and the like can be mentioned. These bifunctional monomers may be used alone or in combination of two or more.

Among the above active energy ray-polymerizable monomers, the trifunctional or higher functional monomer preferably has a molecular weight of 2000 or less, and specific examples thereof include trimethylolpropantriacrylate, ethoxylated trimethylolpropanetriacrylate, and propoxy. Trimethylol Propanetriacrylate, Pentaerythritol Triacrylate, Glycerin Triacrylate, Tetramethylolmethanetriacrylate, Pentaerythritol Tetraacrylate, Pentaerythritol Tetraacrylate, EO Modified Diglycerin Tetraacrylate, Ditrimethylol Propanetetraacrylate, Di Examples thereof include pentaerythritol pentaacrylate and dipentaerythritol hexaacrylate. These polyfunctional monomers may be used alone or in combination of two or more.

In the above ink, the content of the active energy ray-polymerizable monomer is preferably 1 to 95% by mass, more preferably 70 to 95% by mass, from the viewpoint of reactivity. Further, from the viewpoint of reducing the residual monomer, the content of the monofunctional monomer is preferably 20 to 85% by mass, more preferably 50 to 85% by mass.

The above ink may use an acrylate oligomer. The acrylate oligomer is _{an oligomer having one or more acryloyloxy groups (CH 2} = CHCOO−), and preferably has 2 to 6 functional groups. The acrylate oligomer preferably has a molecular weight of 2000 to 20000. The molecular weight is a polystyrene-equivalent weight average molecular weight.

Specific examples of the acrylate oligomer include an amino acrylate oligomer [an _{acrylate oligomer having a plurality of amino groups (-NH 2} )], a urethane acrylate oligomer [an acrylate oligomer having a plurality of urethane bonds (-NHCOO-)], and an epoxy acrylate oligomer [epoxy compound]. Acrylate having a plurality of epoxy acrylates obtained by the reaction between and acrylic acid], a silicone acrylate oligomer [an acrylate oligomer having a plurality of siloxane bonds (-SiO−)], and an ester acrylate oligomer [an acrylate having a plurality of ester bonds (-COO-)]. Acrylate] and butadiene acrylate oligomer [acrylate oligomer having a plurality of butadiene units] and the like. In the above ink, the content of the acrylate oligomer is, for example, 0.4 to 20.0% by mass.

It is preferable to add a photopolymerization initiator, a light stabilizer, a polymerization inhibitor and the like to the ink, and further, in addition to the above-mentioned components, additives commonly used in the ink industry, such as water and organic materials, are used. Solvents, antioxidants, silane coupling agents, plasticizers, rust preventives, pH adjusters, defoamers, charge control agents, stress relievers, penetrants, surface conditioners, etc. within the range that does not impair the object of the present invention. It may be appropriately selected and blended within.

In the above ink, the surface tension at the printing temperature is preferably 20 to 35 mN / m, and the viscosity at the printing temperature is preferably 5 to 15 mPa · s. The temperature of the ink during printing is preferably 35 to 50 ° C.

The ink can be prepared by mixing the coloring pigment, the active energy ray-polymerizable monomer, and various components appropriately selected if necessary.
≪Base material≫
The base material is not particularly limited, and for example, a wooden building material board made of wood such as a single board, plywood, particle board, medium density fiberboard (MDF); a ceramic siding board, a flexible board, a calcium silicate board, etc. , Gypsum slug bar light board, wood piece cement board, asbestos cement board, pulp cement board, precast concrete board, lightweight bubble concrete (ALC) board, ceramic building material board such as gypsum board; and metal building material board such as aluminum, iron, stainless steel And so on. The surface texture of the base material is not particularly limited, and may have a smooth surface or an uneven shape. Further, the base material may be subjected to a base treatment with a sealer, a primer or the like. The thickness of the base material is not particularly limited, and is, for example, 3 to 30 mm.

≪Formation method of ink receiving layer≫
The ink receiving layer of the present invention can be formed by applying the ink receiving layer coating material according to the present invention onto the substrate, drying and curing the ink receiving layer. The coating method is not particularly limited, and examples thereof include air spray coating, airless spray coating, electrostatic coating, roll coater coating, and flow coater coating. The thickness of the ink receiving layer is not particularly limited, and is, for example, 10 to 50 μm.

≪How to form an ink layer≫
The ink layer constituting the printed matter of the present invention is formed by printing an active energy ray-curable ink on the ink receiving layer by a printing means such as printing with an inkjet printer (that is, an inkjet method) and then curing the ink. Can be formed with. The thickness of the ink layer is not particularly limited, and is, for example, 10 to 50 μm.
Examples of the active energy ray used for curing in the present invention include a metal halide lamp, a high-pressure mercury lamp, and an ultraviolet LED, and the wavelength of the activated energy ray to be irradiated overlaps with the absorption wavelength of the photopolymerization initiator. It is preferable that the main wavelength of the active energy ray is 360 to 425 nm.

≪Clear layer≫
For the purpose of protecting the surface of the ink layer, a clear layer arranged so as to cover the ink layer may be provided. The clear layer can be formed, for example, by applying a coating composition for a clear layer to the surfaces of an ink layer and, in some cases, an exposed ink receiving layer, and then forming a film by drying or the like. As a coating method for the clear layer coating composition, a conventionally known coating method can be used without particular limitation. Specifically, air spray coating, airless spray coating, electrostatic coating, roll coater coating, flow coater Painting etc. can be mentioned.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples. In the examples, "parts" and "%" mean parts by mass and% by mass, respectively, unless otherwise specified.

(Synthesis Example 1)
386 parts of ion-exchanged water and polyoxyethylene-1- (allyloxymethyl) alkyl ether sulfate ammonium salt (first) in a five-necked flask equipped with a stirrer, a reflux condenser, a thermometer, a dropping device, and a nitrogen introduction tube. 10 parts of Aqualon KH10) manufactured by Kogyo Seiyaku Co., Ltd. was charged, and the temperature was raised to 80 ° C. while replacing the inside of the reactor with nitrogen. After that, 4 parts of ammonium persulfate was added to the reactor, and then 3 parts of methyl methacrylate, 348 parts of 2-ethylhexyl acrylate, 39 parts of methacrylic acid, and 579 parts of ion-exchanged water, which had been stirred and mixed in a separate container in advance, were added. It was continuously added dropwise over 5 hours. Then, it was aged at 80 ° C. for 5 hours while continuing stirring, and then cooled to room temperature. Then, it was neutralized to pH 9 with a 28 mass% aqueous ammonia solution to obtain a resin particle aqueous dispersion 1.

(Synthesis Examples 2 to 16)
Synthesis was carried out with the monomer composition shown in Table 1 in the same manner as in Synthesis Example 1 to obtain aqueous resin particle dispersions 2 to 16. In the present invention, the calculated Tg is a theoretically calculated value obtained by the following FOX formula.
1 / Tg = W1 / Tg1 + W2 / Tg2 + ... + Wn / Tgn
In the formula, Tg is the calculated Tg (° K), W1, W2, ..., Wn is the mass fraction of each monomer, and Tg1, Tg2, ..., Tgn is the homomer of each monomer. The glass transition temperature (° K) of the polymer.

* For silane coupling agents, only the SP value of organic groups is shown.
CHMA; cyclohexylmethacrylate / ST; styrene / GMA; glycidylmethacrylate / KBM403; 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.)
LA82; 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate (manufactured by ADEKA)
MMA; methyl methacrylate, EA; ethyl acrylate, BA; butyl acrylate, EHA; 2-ethylhexyl acrylate, BMA; butyl methacrylate, MAA; methacrylic acid, DAAM; diacetoneacrylamide, KBM503; 3-methacryloyloxypropyltrimethoxysilane ( Shinetsu Chemical Co., Ltd.)
・ AMA; allyl methacrylate

(Example of preparation of paint for ink receiving layer)
(Examples 1 to 24, Comparative Examples 1 to 8)
The raw materials and titania beads were mixed according to the formulations shown in Tables 2 and 3, and then dispersed in a bead mill. After dispersion, the titania beads were removed to prepare a paint for the ink receiving layer.

1) Titanium oxide, density 3.8 g / cm ³ , (TITONE R-62N, manufactured by Sakai Chemical Co., Ltd.)
2) Heavy calcium carbonate, density 2.7 g / cm ³ , average particle size 2 μm (made by Maruo Calcium)
3) SN Deformer 1316 (manufactured by San Nopco Ltd.)
4) ASE-60 (manufactured by Rohm and Hearth)
5) Proxel AM (manufactured by Arch Chemicals)
6) TINUVIN 1130 (manufactured by BASF)
7) Sanol LS-292 (manufactured by Sankyo Kasei Co., Ltd.)

<Preparation example of active energy ray-curable ink>
According to the formulation shown in Table 4, the raw material and zirconia beads (φ0.5 mm) were mixed and then dispersed by a bead mill. After the dispersion, the zirconia beads were removed to prepare a black UV ink (hereinafter, also referred to as UV ink).

8) MA100 (carbon black pigment, product name manufactured by Mitsubishi Chemical Corporation)
9) Light acrylate PO-A (phenoxyethyl acrylate, trade name manufactured by Kyoeisha Chemical Co., Ltd.) Specific gravity: 1.2, number of functional groups: 1, Tg: -22 ° C, SP value: 10.4
10) Light acrylate P2HA (phenoxydiethylene glycol acrylate, trade name manufactured by Kyoeisha Chemical Co., Ltd.) Specific gravity: 1.2, number of functional groups: 1, Tg: -35 ° C, SP value: 10.2
11) Light acrylate IB-XA (isobornyl acrylate, trade name manufactured by Kyoeisha Chemical Co., Ltd.) Specific gravity: 1.2, number of functional groups: 1, Tg: 94 ° C., SP value: 8.87
12) Light acrylate EC-A (ethoxy-diethylene glycol acrylate, trade name manufactured by Kyoeisha Chemical Co., Ltd.) Specific gravity: 1.2, number of functional groups: 1, Tg: -70 ° C, SP value: 9.96
13) Light acrylate DPM-A (methoxydipropylene glycol acrylate, trade name manufactured by Kyoeisha Chemical Co., Ltd.) Specific gravity: 1.2, number of functional groups: 1, Tg: -30 ° C, SP value: 9.69
14) CTFA (Cyclic trimethylolpropane formal acrylate, trade name manufactured by Osaka Organic Chemical Industry Co., Ltd.) Specific gravity: 1.2, number of functional groups: 1, Tg: 27 ° C, SP value: 9.95
15) 4-HBA (4-hydroxybutyl acrylate, trade name manufactured by Osaka Organic Chemical Industry Co., Ltd.) Specific gravity: 1.2, number of functional groups: 1, Tg: -32 ° C, SP value: 10.8
16) DAAM (diacetone acrylamide, trade name manufactured by Nippon Kasei Chemical Company Limited) Specific gravity: 1.2, number of functional groups: 1, Tg: 77 ° C., SP value: 11.5
17) IDAA (isodecyl acrylate, trade name manufactured by Osaka Organic Chemical Industry Co., Ltd.) Specific gravity: 1.2, number of functional groups: 1, Tg: -62 ° C, SP value: 8.98
18) Light acrylate 1,6HX-A (1,6-hexanediol diacrylate, trade name manufactured by Kyoeisha Chemical Co., Ltd.) Specific gravity: 1.2, number of functional groups: 2, Tg: 63 ° C, SP value: 9.82
19) Light acrylate 1,9ND-A (1,9-nonanediol diacrylate, trade name manufactured by Kyoeisha Chemical Co., Ltd.) Specific gravity: 1.2, Number of functional groups: 2, Tg: 68 ° C., SP value: 9.63
20) Light acrylate TMP-A (trimethylolpropane triacrylate, trade name manufactured by Kyoeisha Chemical Co., Ltd.) Specific gravity: 1.2, number of functional groups: 3, Tg: 62 ° C., SP value: 9.90
21) IRGACURE TPO (acylphosphine oxide-based photopolymerization initiator, trade name manufactured by BASF)
22) IRGACURE 184 (alkylphenone-based photopolymerization initiator, trade name manufactured by BASF)
23) KAYACURE DETX-S (2,4-diethylthioxanthone, trade name manufactured by Nippon Kayaku Co., Ltd.)
24) DISPERBYK-2155 (Product name manufactured by BYK)
25) BYK-UV3500 (Product name manufactured by BYK)

The surface tension of the active energy ray-curable ink was measured at a temperature of 45 ° C. using a tensiometer (CBVP-Z manufactured by Kyowa Surface Chemistry). The viscosity of the active energy ray-curable ink was measured at a temperature of 45 ° C. and a shear rate of 10 s- ¹ using a rheometer (MCR301 manufactured by AntonioPysica).

<Preparation example of paint composition for clear layer (hereinafter referred to as "clear paint")>
The raw materials were mixed according to the formulation shown in Table 5 to prepare a clear paint 1.

26) Polydurex G613 (Acrylic silicone resin emulsion, trade name manufactured by Asahi Kasei Corporation)

<Manufacturing example of building board (decorative test board)>
1. 1. A water-based sealer (manufactured by Dai Nippon Toryo Co., Ltd., product name: Aqueous Mighty Sealer Multi) is applied to the surface of the base material slate plate (150 mm x 70 mm x 5 mm, manufactured by TP Giken Co., Ltd.) with an air spray so ^{that the coating amount is 100 g / m 2.} Then, the substrate was prepared by drying at room temperature for 2 hours.
2. Ink receiving layer sealer With the painted base material heated to 60 ° C, the above-mentioned ink receiving layer paint is applied to the sealer coated surface of the base material to a coating amount of 120 g / m ² (equivalent to a dry film thickness of 30 μm). I painted it with an airless spray. Then, it was dried at 100 degreeC for 3 minutes to form an ink receiving layer. The substrate temperature was measured using an infrared radiation type non-contact thermometer (ISK-8700II, manufactured by AS ONE Corporation).

3. 3. Ink layer After the ink receiving layer is prepared, the gradation pattern of the UV ink (black) prepared above (recording density is from 10%) using an inkjet printer with the substrate temperature adjusted to 50 to 60 ° C. A solid image) recorded stepwise up to 100% in 20% increments) was formed. At this time, the temperature of the ink at the time of ejecting the ink was 45 ° C. After patterning, a metal halide lamp, is irradiated with ultraviolet light at an accumulated light intensity of 300 mJ / cm ² at peak irradiance 800 mW / cm ^2, to cure the ink. The substrate temperature was measured using an infrared radiation type non-contact thermometer (ISK-8700II, manufactured by AS ONE Corporation).

4. Clear layer After the ink was cured, the surface temperature of the cured coating film was adjusted to 50 ° C., and the above-mentioned clear paint was applied so that the coating amount was 80 g / m ² (equivalent to a dry film thickness of 25 μm). .. After painting, it was dried at 80 ° C. for 20 minutes to form a clear layer. The surface temperature was measured using an infrared radiation type non-contact thermometer (ISK-8700II, manufactured by AS ONE Corporation).

[Evaluation method]
The ink absorption rate of the ink receiving layer, print evaluation (color development, dot diameter), adhesion, water resistance, weather resistance, and monomer emission rate of the printed matter after the ink layer was laminated or after the clear layer was laminated were evaluated by the following methods. .. The measurement results are shown in Tables 6 to 11. Unless otherwise specified, the evaluation was performed in an atmosphere of 23 ° C. and 50% RH.
(1) Color development The color development was evaluated by observing the gradation pattern one day after the production of the printed matter with the naked eye and with a microscope. The evaluation criteria are as follows.
〇: The original color of the ink is printed evenly and evenly, and there is no bleeding.
X: The gradation pattern has unevenness, rubbing, and / or bleeding.

(2) Dot diameter With respect to the gradation pattern one day after the production of the printed matter, the diameters of dots at arbitrary five points were measured with a microscope, and the average value was calculated.

(3) Adhesiveness (based on JIS K5600-5-6: 1999)
A cutter knife was used to make cuts in the produced printed matter at intervals of 2 mm in length and width, 100 squares were prepared, and a cellophane tape (registered trademark) peeling test was performed. The evaluation criteria are as follows.
◯: Classification 0 to 1
Δ: Classification 2
×: Classification 3 to 5
The categories 0 to 5 described in 8.3 of JIS K 5600-5-6: 1999 are as follows.
-Category 0: The edges of the cut are completely smooth, and there is no peeling in the eyes of any grid.
-Category 1: The residual rate of the laminated coating film is 95 to 99%.
-Category 2: The residual rate of the laminated coating film is 85% or more and less than 95%.
-Category 3: The residual rate of the laminated coating film is 65% or more and less than 85%.
-Category 4: The residual rate of the laminated coating film is 0% or more and less than 65%.
-Category 5: Any degree of peeling that cannot be classified even in Category 4.

(4) Water resistance (based on JIS K 5600-6-2: 1999)
The produced printed matter was immersed in a constant temperature water bath kept at 40 ° C., and after 240 hours, it was taken out and dried. After that, the appearance such as swelling and whitening that occurred was observed, and the adhesiveness was evaluated by the same method as the method (2) above. The evaluation criteria are as follows.
However, Examples 31 and 32 and Comparative Examples 10 to 12 were not evaluated.
⊚: There is no appearance abnormality such as swelling and whitening, and the adhesiveness is classified as 0.
◯: There is no appearance abnormality such as swelling and whitening, and the adhesiveness is classification 1. Δ: There is no appearance abnormality such as swelling and whitening, and the adhesiveness is classification 2 to 3.
X: Appearance abnormalities such as swelling and whitening are observed. Adhesion is classified into 4-5.

(5) Accelerated weather resistance (based on JIS K 5600-7-7: 2008)
The produced printed matter was subjected to an accelerated weather resistance test by a weatherometer Ci4000 (manufactured by Atlas) according to the xenon lamp method described in JIS K 5600-7-7. The test time was up to 1000 hours, the appearance of the coating film was visually evaluated, and the adhesiveness was evaluated by the same method as the method (2) above. The evaluation criteria are as follows.
However, Examples 31 and 32 and Comparative Examples 10 to 12 were not evaluated.
〇: There is no appearance abnormality such as swelling, chalking, cracks, etc., and the adhesiveness is classified as 0 to 1.
Δ: There is no appearance abnormality such as swelling, chalking, and cracks, and the adhesiveness is classified into 2 to 3.
X: Appearance abnormalities such as swelling, chalking, and cracks are observed. Adhesion is classified into 4-5.

(6) Ink Absorption Rate Measurement Method The ink receiving layer paint was applied to a hard PVC plate preheated to 60 ° C. using a 20 mil applicator, and dried at 100 ° C. for 3 minutes (leeward). The dry film was peeled off, cut into a length of 50 mm and a width of 50 mm, and the mass was measured. 100 g of UV ink (black) was placed in a 200 ml glass container, and the cut dry film was further placed. After soaking at 50 ° C. for 24 hours, the membrane is taken out, placed on a Kim towel (Crecia Co., Ltd.), and a Kim towel is placed on the above-mentioned membrane placed on the Kim towel to sandwich the membrane, and a weight of 500 g is applied to the surface of the membrane. The UV ink was removed and the mass of the dry film was measured. The ink absorption rate was calculated by the following formula from the mass change before and after immersion of the dry film.
Calculation formula
{(Mass after immersion-Mass before immersion) / Mass before immersion} x 100 = Ink absorption rate (%)

(7) Elongation rate of coating film The paint for the ink receiving layer was applied to a polypropylene plate using a 20-mil applicator, and dried at 23 ° C. for 24 hours. Then, it was dried at 80 ° C. for 3 hours and then dried at 120 ° C. for 30 minutes. Then, the obtained dry film was peeled off and cut into a length of 70 mm and a width of 5 mm to obtain a test piece.
The test piece was subjected to a tensile test at a speed of 5 mm / min using an Autograph AG-100KNI type manufactured by Shimadzu Corporation at 23 ° C. and 50% RH, and the elongation rate of the coating film was calculated by the following formula. .. Here, the length of the test piece in the tensile test was set to 50 mm.
{(Test piece length at break in tensile test-Test piece length before test) / (Test piece length before test)} x 100 = Elongation rate of coating film (%)

(8) Monomer emission rate of the ink layer The monomer emission amount was calculated by gas chromatography measurement using a small chamber according to JIS A 1901: 2015.
The inside of the 1.20 L chamber was set to a temperature of 28 ° C., a humidity of 50% RH, and a ventilation rate of 0.5 times / h, and stabilized for 1 hour.
2. The air in the chamber was sampled, and the amount of monomer detected (background) before setting the test piece was measured.
3. 3. The test piece was set in the chamber and the monomer was allowed to dissipate for 2 hours. The measurement was performed when the temperature of the test piece dropped to 28 ° C. one hour after the test piece was prepared.
4. The air in the chamber was sampled, and the amount of monomer detected after the test piece was placed was measured.
5. The monomer concentration was calculated using the calibration curve prepared from the standard reagent, and the emission rate of each monomer was calculated from the following formula.
(formula)
EFa = Ct × n / L
EFa: Monomer emission rate per unit area (μg / m ² · h)
n: Ventilation frequency (times / h)
Ct: Concentration of monomer in the chamber at elapsed time t L: Sample load factor (m ² / m ³ ) (Ratio of small chamber volume to surface area of test piece)
<Evaluation result>

*: Indicates that the dry film obtained from the ink receiving layer paint is completely dissolved in the UV ink (black).

As described above, the present invention is excellent in ink absorption rate, print evaluation (color development, dot diameter), and adhesiveness of the ink receiving layer, and further, the amount of monomer emitted from the ink layer is small.

Claims (5)

A printed matter formed by laminating an ink receiving layer having an ink absorption rate of 100% or less on the surface of a base material and an ink layer obtained by curing an active energy ray-curable ink containing a polymerizable compound on the surface of the ink receiving layer. It ’s a manufacturing method ,
The proportion of the monofunctional monomer contained in the polymerizable compound is 50% by mass or more, and the content is 50% by mass or more.
The ink receiving layer is formed of a water-based paint containing a cross-linking agent.
The glass transition temperature of the polymer of the polymerizable compound is 45 to 25 ° C.
Printed matter manufacturing method . The printed matter according to claim 1, wherein the ink receiving layer contains a polymer containing 25 to 85% by mass of at least one structural unit derived from an ethylenically unsaturated monomer having a solubility parameter of 9.50 to 13.0 . Manufacturing method . The method for producing a printed matter according to claim 1 or 2, wherein the elongation rate of the ink receiving layer is 10 to 30%. The method for producing a printed matter according to any one of claims 1 to 3, wherein the content of the pigment contained in the ink receiving layer is 35 to 85% by mass with respect to the component forming the ink receiving layer . The method for producing a printed matter according to any one of claims 1 to 4, wherein the resin contained in the ink receiving layer has a ratio of structural units derived from a monomer having a cyclic structure of more than 0 and 28% by mass or less.