JP7484571B2 - Manufacturing method of printed matter - Google Patents

Description

The present invention relates to a method for producing a printed matter.

Flooring, wallpaper and other materials that have been printed with desired images and given a design by embossing or other methods are used for the floors, interior walls, ceilings and other areas of buildings. Attempts have also been made to improve the durability of flooring and wallpaper by coating them with ultraviolet (UV) curing materials or electron beam curing materials.

Furthermore, in recent years, technology has been developed to print desired images on embossed flooring, wallpaper, and the like using an inkjet method. One such technology has been proposed, for example, as a method for producing foamed wallpaper that has a foam layer, an image-forming layer, and a surface protective layer, the foam layer containing a thermoplastic resin and a foaming agent, and the image-forming layer and the surface protective layer can be crosslinked or cured by electron beam irradiation (see, for example, Patent Document 1).

The present invention aims to provide a method for producing printed matter that has excellent design and image quality due to its uneven shape, and can produce printed matter that can maintain the excellent design and image quality due to its uneven shape for a long period of time.

As a means for solving this problem, the method for producing a printed matter of the present invention comprises the steps of:
a foam layer forming step of forming a foam layer containing a foaming agent;
an ink-receiving layer forming step of applying an ink-receiving layer forming liquid containing a polymerizable compound a onto the foam layer to form an ink-receiving layer;
an image forming step of applying an ink containing a coloring material and a polymerizable compound b onto the ink receiving layer to form an image;
A foaming step of heating the foam layer to foam it ,
The ink receiving layer forming liquid and the ink are cured at the same time .

The present invention provides a method for producing printed matter that can produce printed matter that has excellent design and image quality due to its uneven shape and can retain the excellent design and image quality due to its uneven shape for a long period of time.

FIG. 1 is a schematic diagram showing an example of a printing production apparatus of the present invention. FIG. 2 is a schematic diagram showing another example of the apparatus for producing printed matter of the present invention. FIG. 3A is a schematic diagram showing an example of a flow of producing a printed matter in the method for producing a printed matter of the present invention. FIG. 3B is a schematic diagram showing an example of a flow of producing a printed matter in the method for producing a printed matter of the present invention. FIG. 3C is a schematic diagram showing an example of a flow of producing a printed matter in the method for producing a printed matter of the present invention. FIG. 3D is a schematic diagram showing an example of a flow of producing a printed matter in the method for producing a printed matter of the present invention. FIG. 3E is a schematic diagram showing an example of a flow of producing a printed matter in the method for producing a printed matter of the present invention. FIG. 3F is a schematic diagram showing an example of a flow of producing a printed matter in the method for producing a printed matter of the present invention. FIG. 3G is a schematic diagram showing an example of a flow of producing a printed matter in the method for producing a printed matter of the present invention.

(Printed matter manufacturing method, printed matter manufacturing device)
The method for producing a printed matter of the present invention includes a foam layer forming step of forming a foam layer containing a foaming agent, an ink receiving layer forming step of forming an ink receiving layer containing a polymer of polymerizable compound a on the foam layer, an image forming step of applying an ink containing a colorant and polymerizable compound b onto the ink receiving layer to form an image, and a foaming step of heating the foam layer to foam it, and preferably includes at least one of a transparent layer forming step, a foaming inhibitor applying step, a substrate surface modifying step, a foam layer surface modifying step, a filler-containing layer forming step, and an adhesive layer forming step, and further includes other steps as necessary.

The apparatus for producing printed matter of the present invention has a foam layer forming means for forming a foam layer containing a foaming agent, an ink receiving layer forming means for forming an ink receiving layer containing a polymer of polymerizable compound a on the foam layer, an image forming means for applying an ink containing a coloring material and polymerizable compound b on the ink receiving layer to form an image, and a foaming means for heating and foaming the foam layer, and preferably has at least one of a transparent layer forming means, a foam inhibitor applying means, a substrate surface modifying means, a foam layer surface modifying means, a filler-containing layer forming means, and an adhesive layer forming means, and further has other means as necessary.

The method for producing a printed matter of the present invention can be suitably carried out by the apparatus for producing a printed matter of the present invention, the foam layer forming step can be suitably carried out by a foam layer forming means, the ink receiving layer forming step can be suitably carried out by an ink receiving layer forming means, the image step can be suitably carried out by an image means, the foaming step can be suitably carried out by a foaming means, the transparent layer forming step can be suitably carried out by a transparent layer forming means, the foaming inhibitor applying step can be suitably carried out by a foaming inhibitor applying means, the substrate surface modifying step can be suitably carried out by a substrate surface modifying means, the foam layer surface modifying step can be suitably carried out by a foam layer surface modifying means, the filler-containing layer forming step can be suitably carried out by a filler-containing layer forming means, the adhesive layer forming step can be suitably carried out by an adhesive layer forming means, and the other steps can be carried out by other means.

The method for producing printed matter of the present invention is based on the inventors' findings that conventional methods for producing printed matter may not be able to impart a sufficient uneven shape to the printed matter, and may result in insufficient design due to the uneven shape and in insufficient quality (color development and durability) of the image formed on the uneven shape.

In the conventional method for producing printed matter, for example, embossing using a mold is required to impart a concave-convex shape, which makes it difficult to produce a small number of items (small-lot production), resulting in high production costs. Furthermore, in the conventional method for producing printed matter, even when the concave-convex shape is formed by foaming the foam layer, when an image is formed on the concave-convex shape, the color development of the image is insufficient, resulting in uneven density. In addition, in the conventional method for producing printed matter, when the concave-convex shape is formed by foaming the foam layer, the durability of the image formed on the foam layer is insufficient, and the image may be scratched due to external impact, or the foam layer may peel off from the image.

Therefore, the present inventors have intensively studied a method for producing a printed matter that can produce a printed matter that has excellent design and image quality due to the uneven shape and can maintain the excellent design and image quality due to the uneven shape for a long period of time, and have come up with the present invention. That is, the present inventors have found that a printed matter that has excellent design and image quality due to the uneven shape and can maintain the excellent design and image quality due to the uneven shape for a long period of time can be produced by a method for producing a printed matter that includes a foam layer forming step of forming a foam layer containing a foaming agent, an ink receiving layer forming step of forming an ink receiving layer containing a polymer of polymerizable compound a on the foam layer, an image forming step of applying an ink containing a coloring material and polymerizable compound b on the ink receiving layer to form an image, and a foaming step of heating the foam layer to foam it.

Here, in the method for producing a printed matter of the present invention, an ink receiving layer containing a polymer of polymerizable compound a is formed on a foam layer, and an ink containing a coloring material and polymerizable compound b is applied onto the ink receiving layer to form an image. In this manner, in the method for producing a printed matter of the present invention, the material of the ink receiving layer and the ink each contain a polymerizable compound, so that the affinity between the ink receiving layer and the ink is increased. Therefore, in the method for producing a printed matter of the present invention, by forming an image by applying ink onto the ink receiving layer, the color development of the image formed with the ink can be improved, and the durability of the image against external impacts can also be improved.
Furthermore, in the method for producing a printed matter of the present invention, a foam layer containing a foaming agent is formed and the foam layer is foamed. In this manner, the method for producing a printed matter of the present invention can easily impart a design property due to an excellent uneven shape to the printed matter.

In this way, the method for producing a printed matter of the present invention includes a foam layer forming process, an ink receiving layer forming process, an image forming process, and a foaming process, and thus produces a printed matter that has excellent design and image quality due to the uneven shape, and can maintain the excellent design and image quality due to the uneven shape for a long period of time.

<Foam layer forming step, foam layer forming means>
The foam layer forming step is a step of forming a foam layer containing a foaming agent.
The foam layer forming means is a means for forming a foam layer containing a foaming agent.
The foam layer forming means is not particularly limited and can be appropriately selected depending on the purpose. For example, it can be a combination of a known material applying means (e.g., a coating means, a discharge means, etc.) and a known energy applying means (e.g., a thermal energy applying means, an active energy ray irradiation means, etc.).

The foam layer forming step is not particularly limited as long as it can form a foam layer, but for example, it is preferable to form the foam layer by applying a foam layer forming liquid containing a foaming agent onto a substrate by a material applying means to form a film, and then curing the foam layer by an energy applying means. In other words, in the foam layer forming step, it is preferable to form the foam layer by applying a foam layer forming liquid containing a foaming agent onto a substrate, and then curing the foam layer forming liquid.
Furthermore, the timing for curing the foam layer forming liquid is not particularly limited and can be appropriately selected depending on the purpose. For example, when curing the ink that forms the ink receiving layer or image described below, the foam layer and at least one of the ink that forms the ink receiving layer and the image may be cured together.

<<Substrate>>
The substrate to which the foam layer forming liquid is applied is not particularly limited and can be appropriately selected depending on the purpose. Examples of the substrate include resin films, resin-impregnated papers, synthetic papers made of synthetic fibers, natural papers, sheets such as nonwoven fabrics, cloths, wood boards, metal boards, glass boards, ceramic boards, building materials, and the like.

The resin film is not particularly limited and can be appropriately selected depending on the purpose. Examples of the resin film include polyester films; polypropylene films; polyethylene films; plastic films such as nylon, vinylon, and acrylic films, and films laminated with these films.
From the standpoint of strength, the resin film is preferably uniaxially or biaxially stretched.

The nonwoven fabric is not particularly limited and may be appropriately selected depending on the purpose. For example, it may be formed by scattering polyethylene fibers in a sheet form and thermocompressing the same.
The wooden board is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include MDF, HDF, particle board, plywood such as veneer, decorative board with a sheet attached to the surface, etc. The thickness of these boards can be, for example, 2 mm to 30 mm.
The glass plate is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include float glass, colored glass, tempered glass, wired glass, ground glass, frosted glass, mirror glass, etc. The thickness of these glass plates can be, for example, 0.3 mm to 20 mm.
The building materials are not particularly limited and can be appropriately selected depending on the purpose. Examples of the building materials include thermosetting resins used in flooring, wallpaper, interior materials, wall panels, baseboards, ceiling materials, pillars, etc., fiberboards, particle boards, and the above-mentioned materials with a decorative plate of thermosetting resin, olefin, polyester, PVC, etc. provided on the surface.

<<Foam layer forming liquid>>
The foam layer forming liquid contains a foaming agent, and preferably contains a liquid composition, and further contains other components as necessary.

- Foaming agent -
The foaming agent is not particularly limited as long as it is a material whose volume expands when heated, and can be appropriately selected according to the purpose, and examples thereof include thermally expandable microcapsules and thermally decomposable foaming agents. Among these, thermally expandable microcapsules are preferred because they have a high volume expansion ratio and can form uniform and small independent bubbles. In the following, the foaming agent may also be referred to as a volume expansion agent.

Thermally expandable microcapsules are particles with a core-shell structure in which a foaming agent is encapsulated in a thermoplastic resin. When heated, the thermoplastic resin in the shell begins to soften, and the vapor pressure of the encapsulated foaming compound increases to a level sufficient to deform the particles, causing the thermoplastic resin in the shell to stretch and expand. Examples of foaming compounds include low-boiling aliphatic hydrocarbons.

As the thermally expandable microcapsules, commercially available products can be used, such as the Advancell EM series manufactured by Sekisui Chemical Co., Ltd., the Expancell DU, WU, MB, SL, and FG series manufactured by AkzoNovel (sold in Japan by Nippon Phillite Co., Ltd.), the Matsumoto Microsphere F and FN series manufactured by Matsumoto Yushi Seiyaku Co., Ltd., and the Kureha Microsphere H750, H850, and H1100 manufactured by Kureha Corporation. These may be used alone or in combination of two or more types.

Examples of the thermally decomposable foaming agent include organic foaming agents and inorganic foaming agents.
Examples of organic blowing agents include azodicarboxylic acid amide (ADCA), azobisisobutylnitrile (AIBN), p,p'-oxybisbenzenesulfonylhydrazide (OBSH), dinitrosopentamethylenetetramine (DPT), etc. These may be used alone or in combination of two or more.

Examples of inorganic foaming agents include bicarbonates such as sodium bicarbonate, carbonates, and combinations of bicarbonates and organic acid salts.

The content of the foaming agent in the curable composition is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 1% by mass or more and 20% by mass or less, and more preferably 5% by mass or more and 15% by mass or less, based on the total amount of the curable composition.

--Liquid composition--
The liquid composition is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include water, aqueous organic solvents, oily organic solvents, and polymerizable solvents. The liquid composition can be selected, for example, depending on the liquid contact with the foaming agent (whether the foaming agent is attacked by the liquid composition, or the foaming function is inhibited). The SP value (solubility parameter) can be used as a criterion for the liquid contact in the liquid composition, and it is preferable to select a liquid with an SP value far from the foaming agent so that it is not compatible with the foaming agent.
Here, the liquid composition plays a role as a dispersion medium for the foaming agent, for example, but when the liquid composition is a polymerizable solvent (polymerizable compound), it can also play a role in forming a foam layer. When the liquid composition is a liquid that is not a polymerizable solvent, it is preferable to further add a resin so that the liquid composition can form a foam layer.

Examples of aqueous organic solvents include polyhydric alcohols such as methanol, ethanol, 1-propanol, 2-propanol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, glycerin, 1,2,6-hexanetriol, 2-ethyl-1,3-hexanediol, 1,2,4-butanetriol, 1,2,3-butanetriol, and petriol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, and the like. Examples of suitable amines include polyhydric alcohol alkyl ethers such as ethyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether; polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether; nitrogen-containing heterocyclic compounds such as N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethylimidazolidinone, and ε-caprolactam; amides such as formamide, N-methylformamide, and N,N-dimethylformamide; amines such as monoethanolamine, diethanolamine, triethanolamine, monoethylamine, diethylamine, and triethylamine; sulfur-containing compounds such as dimethyl sulfoxide, sulfolane, and thiodiethanol; propylene carbonate, ethylene carbonate, γ-butyrolactone, and acetone.

Examples of oily organic solvents include hydrocarbons such as dodecane, isododecane, hexadecane, isohexadecane, liquid paraffin, squalane, squalene, polybutene, polyisobutylene, cyclopentane, cyclohexane, polybutadiene, hydrogenated polybutadiene, polyisoprene, and hydrogenated polyisoprene.
Examples of ester oils include isopropyl myristate, isopropyl palmitate, cetyl octanoate, octyldodecyl myristate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyldecyl dimethyloctanoate, cetyl lactate, lanolin acetate, isocetyl stearate, isocetyl isostearate, di-2-ethylhexyl sebacate, di-2-hexyldecyl myristate, di-2-hexyldecyl palmitate, di-2-hexyldecyl adipate, and diisopropyl sebacate.
Examples of higher fatty acids include isostearic acid, oleic acid, palmitic acid, lauric acid, myristic acid, behenic acid, linoleic acid, linolenic acid, etc., and in particular, oleic acid and the like which are liquid at room temperature are preferred. Examples of higher alcohols include isostearyl alcohol, oleyl alcohol, octyldodecanol, cholesterol, stearyl alcohol, cetyl alcohol, decyltetradecanol, hexyldecanol, behenyl alcohol, lauryl alcohol, lanolin alcohol, myristyl alcohol, batyl alcohol, etc., and in particular, oleyl alcohol and the like which are liquid at room temperature are preferred.
Examples of silicones include dimethylpolysiloxane, cyclomethicone, diphenylpolysiloxane, and alkylpolysiloxane. Other examples include compounds other than aqueous organic solvents, such as methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl lactate, ethyl ethoxypropionate, butanol, normal hexane, cyclohexane, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, tetrahydrofuran, dioxane, toluene, ethylbenzene, acetophenone, and benzyl alcohol.

-Polymerizable solvent (polymerizable compound)-
The polymerizable solvent (polymerizable compound) is not particularly limited as long as it is a compound that can be polymerized by the application of energy or the like, and can be appropriately selected depending on the purpose. Examples of the polymerizable solvent include a monofunctional monomer, a polyfunctional monomer, and a combination of a monofunctional monomer and a polyfunctional monomer.

- Monofunctional monomer -
The monofunctional monomer has, for example, one vinyl group, one acryloyl group, or one methacryloyl group in the molecular structure.
Examples of monofunctional monomers include γ-butyrolactone (meth)acrylate, isobornyl (meth)acrylate, formalized trimethylolpropane mono(meth)acrylate, trimethylolpropane (meth)acrylic acid benzoate, (meth)acryloylmorpholine, 2-hydroxypropyl (meth)acrylamide, N-vinylcaprolactam, N-vinylpyrrolidone, N-vinylformamide, cyclohexanedimethanol monovinyl ether, hydroxyethyl vinyl ether, diethylene glycol monovinyl ether, dicyclopentadiene vinyl ether, tricyclodecane vinyl ether, benzyl vinyl ether, ethyloxetane methyl vinyl ether, hydroxybutyl vinyl ether, ethyl vinyl ether, ethoxy (4) nonylphenol (meth)acrylate, benzyl (meth)acrylate, and caprolactone (meth)acrylate. These may be used alone or in combination of two or more.
Among these, isobornyl (meth)acrylate is preferred because it has a high glass transition temperature (Tg) and good fastness.
The content of the monofunctional monomer is preferably from 80% by mass to 99.5% by mass, and more preferably from 90% by mass to 95% by mass, based on the total amount of the curable composition.

- Multifunctional monomer -
The polyfunctional monomer is, for example, a compound having two or more vinyl groups, acryloyl groups, or methacryloyl groups in the molecular structure.
Examples of polyfunctional monomers include ethylene glycol di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol dimethacrylate [CH ₂ ═CH-CO-(OC ₂ H ₄ )n-OCOCH=CH ₂ (n≈9), (n≈14), (n≈23)], dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol dimethacrylate [CH ₂ ═C(CH ₃ )-CO-(OC ₃ H ₆ ) _n -OCOC(CH ₃ )=CH ₂ (n≒7)], 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, propylene oxide modified bisphenol A di(meth)acrylate, polyethylene glycol di(meth)acrylate, dipentaerythritol hexa(meth)acrylate, propylene oxide modified tetra(meth)acrylate, Lamethylolmethane tetra(meth)acrylate, dipentaerythritol hydroxypenta(meth)acrylate, caprolactone modified dipentaerythritol hydroxypenta(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethylene oxide modified trimethylolpropane tri(meth)acrylate, propylene oxide modified trimethylolpropane tri(meth)acrylate, caprolactone Examples of the vinyl ether derivatives include ethylene glycol divinyl ether, ... These may be used alone or in combination of two or more.

For polyfunctional monomers, it is preferable that the [molecular weight/functional number] is, for example, 250 or more, in order to achieve both design (volume expansion) and robustness.

The content of the polyfunctional monomer and oligomer in the polymerizable compound is preferably 0.5% by mass to 20% by mass, more preferably 5% by mass to 10% by mass, based on the total amount of the polymerizable compound. If the content is 10% by mass or less, there is an advantage that both designability (foamability) and robustness can be achieved.
The content of the polymerizable compound is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 60% by mass to 90% by mass, more preferably 70% by mass to 85% by mass, based on the total amount of the foam layer forming liquid. When it is 70% by mass or less, the adhesiveness of the foaming agent in the foam layer can be increased.

-Other ingredients-
Other components in the foam layer forming liquid are not particularly limited and can be appropriately selected according to the purpose, and examples thereof include binder resins, polymerization initiators, fillers, foaming accelerators, dispersants, colorants, organic solvents, antiblocking agents, thickeners, preservatives, stabilizers, deodorants, fluorescent agents, ultraviolet blocking agents, surfactants, etc. Among these, when the liquid composition is a polymerizable solvent (polymerizable compound), it is preferable to contain a polymerization initiator. Also, when the liquid composition is not a polymerizable compound, it is preferable to contain a binder resin.

--Binder resin--
There are no particular limitations on the binder resin as long as it is capable of retaining the foaming agent, and it can be appropriately selected depending on the purpose. Examples of the binder resin include water-soluble resins, emulsion resins, and other resins.

Examples of water-soluble resins include natural plant polymers such as gum arabic, tragan gum, guar gum, karaya gum, locust bean gum, arabinogalactone, pectin, and quince seed starch, seaweed polymers such as alginic acid, carrageenan, and agar, animal polymers such as gelatin, casein, albumin, and collagen, microbial polymers such as xanthan gum and dextran, and shellac, and semi-synthetic cellulose polymers such as methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, and carboxymethylcellulose, and sodium starch glycolate. Examples of purely synthetic polymers include vinyl polymers such as polyvinyl alcohol, polyvinylpyrrolidone, and polyvinyl methyl ether, non-crosslinked polyacrylamide, polyacrylic acid and its alkali metal salts, acrylic resins such as water-soluble styrene-acrylic resin, water-soluble styrene-maleic acid resin, water-soluble vinylnaphthalene-acrylic resin, water-soluble vinylnaphthalene-maleic acid resin, and alkali metal salts of β-naphthalenesulfonic acid formalin condensate.
Examples of emulsion resins include acrylic resins, vinyl acetate resins, styrene-butadiene resins, vinyl chloride resins, acrylic-styrene resins, butadiene resins, and styrene resins.
Other resins that can be used as the binder resin include, for example, polyester resins and acrylic resins that are soluble in oil-based organic solvents.

--Polymerization initiator--
Examples of the polymerization initiator include a thermal polymerization initiator, a photopolymerization initiator, etc. Among these, a photopolymerization initiator is more preferred from the viewpoints of designability due to the uneven shape and durability of image quality.
The photopolymerization initiator may be any one that can generate active species such as radicals or cations by the energy of active energy rays and initiate polymerization of a polymerizable compound. As such a polymerization initiator, known radical polymerization initiators, cationic polymerization initiators, base generators, etc. may be used alone or in combination of two or more kinds, and among these, it is preferable to use a radical polymerization initiator.
In order to obtain a sufficient curing rate, the content of the polymerization initiator is preferably from 1 mass % to 20 mass %, more preferably from 5 mass % to 15 mass %, based on the total amount of the curable composition.
Examples of the radical polymerization initiator include aromatic ketones, acylphosphine oxide compounds, aromatic onium salt compounds, organic peroxides, thio compounds (e.g., thioxanthone compounds, thiophenyl group-containing compounds, etc.), hexaarylbiimidazole compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having a carbon-halogen bond, and alkylamine compounds.

In addition to the above polymerization initiator, a polymerization promoter (sensitizer) can also be used in combination.
The polymerization accelerator is not particularly limited and can be appropriately selected depending on the purpose. Examples of the accelerator include amine compounds such as trimethylamine, methyldimethanolamine, triethanolamine, p-diethylaminoacetophenone, ethyl p-dimethylaminobenzoate, 2-ethylhexyl p-dimethylaminobenzoate, N,N-dimethylbenzylamine, and 4,4'-bis(diethylamino)benzophenone.
The content of the polymerization accelerator is not particularly limited, and may be appropriately set depending on the polymerization initiator used and its amount.

--Surfactants--
A surfactant may be added to lower the surface tension to adjust leveling when applied to a substrate and to adjust the spread of the foam inhibitor.
Examples of the surfactant include glycerin fatty acid esters, sorbitan fatty acid esters, fatty acid esters of polyethylene glycol, glycerin fatty acid esters such as glyceryl monostearate, glyceryl monooleate, diglyceryl monostearate, and diglyceryl monoisostearate, glycol fatty acid esters such as propylene glycol monostearate, sorbitan fatty acid esters such as sorbitan monostearate and sorbitan monooleate, sucrose stearate, POE (4.2) lauryl ether, POE (40) hydrogenated castor oil, POE (10) cetyl ether, and POE (9) lauryl ether, POE(10) oleyl ether, POE(20) sorbitan monooleate, POE(6) sorbitan monolaurate, POE(15) cetyl ether, POE(20) sorbitan monopalmitate, POE(15) oleyl ether, POE(100) hydrogenated castor oil, POE(20) POP(4) cetyl ether, POE(20) cetyl ether, POE(20) oleyl ether, POE(20) stearyl ether, POE(50) oleyl ether, POE(25) cetyl ether, POE(25) lauryl ether, POE(30) cetyl ether, POE(40) cetyl ether, etc. These may be used alone or in combination of two or more.
The surfactant is preferably contained in an amount of, for example, 0.1% by mass or more and 2% by mass or less based on the total amount of the foam layer forming liquid.

--filler--
Examples of fillers include aluminum hydroxide, magnesium hydroxide, barium hydroxide, calcium carbonate, magnesium carbonate, calcium sulfate, barium sulfate, ferrous hydroxide, basic zinc carbonate, basic lead carbonate, silica sand, clay, talc, silicas, titanium dioxide, magnesium silicate, etc. These may be used alone or in combination of two or more. Among these, calcium carbonate, magnesium carbonate, aluminum hydroxide, and magnesium hydroxide are preferred.

--Foaming accelerator--
The foaming accelerator is not particularly limited and can be appropriately selected depending on the purpose. Examples of the foaming accelerator include zinc naphthenate, zinc acetate, zinc propionate, zinc 2-ethylpentanoate, zinc 2-ethyl-4-methylpentanoate, zinc 2-methylhexanoate, zinc 2-ethylhexanoate, zinc isooctanoate, zinc n-octanoate, zinc neodecanoate, zinc isodecanoate, zinc n-decanoate, zinc laurate, zinc myristate, zinc palmitate, zinc stearate, zinc isostearate, and 12-hydroxyethyl 1,2-dihydro-2 ... Examples of such compounds include zinc hydroxystearate, zinc behenate, zinc oleate, zinc linoleate, zinc linoleate, zinc ricinoleate, zinc benzoate, zinc o-, m- or p-toluate, zinc p-t-butylbenzoate, zinc salicylate, zinc phthalate, zinc salts of monoalkyl (C4-18) phthalates, zinc dehydroacetate, zinc dibutyldithiocarbamate, zinc aminocrotonate, zinc salts of 2-mercaptobenzothiazole, zinc pyrithione, and zinc complexes of urea or diphenylurea. These compounds may be used alone or in combination of two or more.

--Thickener--
Examples of the thickener include polycyanoacrylate, polylactic acid, polyglycolic acid, polycaprolactone, polyacrylic acid alkyl ester, and polymethacrylic acid alkyl ester.

--Preservative--
Examples of preservatives include those that have been used conventionally and do not initiate polymerization of monomers, such as potassium sorbate, sodium benzoate, sorbic acid, and chlorocresol.

--Stabilizer--
The stabilizers include, for example, anionic stabilizers, free radical stabilizers, etc., which serve the purpose of inhibiting polymerization of monomers during storage.
Examples of the anionic stabilizer include metaphosphoric acid, maleic acid, maleic anhydride, alkylsulfonic acid, phosphorus pentoxide, iron (III) chloride, antimony oxide, 2,4,6-trinitrophenol, thiol, alkylsulfonyl, alkylsulfone, alkylsulfoxide, alkyl sulfite, sultone, sulfur dioxide, and sulfur trioxide.
Free radical stabilizers include, for example, hydroquinone, catechol, or derivatives thereof.

The foam layer forming liquid used in the present invention can be prepared using the various components as described above. The preparation means and conditions are not particularly limited. For example, the foam layer forming liquid can be prepared by putting the foaming agent and the liquid composition into a dispersing machine such as a ball mill, a Kitty mill, a disk mill, a pin mill, or a Dyno mill, dispersing them, and mixing them with a polymerization initiator, a surfactant, etc.
The static surface tension of the foam layer forming liquid used in the present invention can be measured by, for example, a plate method or a ring method using an automatic surface tensiometer DY-300 manufactured by Kyowa Interface Science Co., Ltd. The static surface tension may be appropriately adjusted depending on the application and the means of application, but is preferably 15 mN/m or more and 50 mN/m or less at 25° C.
The viscosity of the foam layer forming liquid can be measured, for example, by using a rheometer MCR301 manufactured by Anton Paar using a cone plate CP25-1, with a shear rate of 10/s and a suitable setting in the range of 20° C. to 65° C. The viscosity may be adjusted as appropriate depending on the application and means of application, but is preferably 10 mPa·s or more and 20,000 mPa·s or less at 25° C.

The method for applying the foam layer forming liquid onto the substrate is not particularly limited and can be appropriately selected depending on the purpose. Examples include coating methods such as knife coating, nozzle coating, die coating, lip coating, comma coating, gravure coating, rotary screen coating, reverse roll coating, roll coating, spin coating, kneader coating, bar coating, blade coating, casting, dipping, curtain coating, and inkjet methods.

In addition, in the present invention, in the foam layer forming step, it is preferable to apply a foam layer forming liquid containing a foaming agent and a polymerizable solvent (polymerizable compound) as a liquid composition onto the substrate, and then harden the foam layer forming liquid to form the foam layer.

Here, when the foam layer forming liquid is hardened, the hardening method of the foam layer forming liquid is not particularly limited and can be appropriately selected depending on the purpose. For example, the hardening can be performed by an energy imparting step.
The energy application step is a step of applying energy to a target layer, and can be carried out, for example, by an energy application means.
Examples of the energy include thermal energy and active energy rays.

When the energy is thermal energy, for example, the foam layer may be hardened and foamed by applying thermal energy to the foam layer. In other words, when applying thermal energy to the curable composition to harden it, a foaming step for foaming the foaming agent may be performed all at once. In addition, when applying a foaming inhibitor to the foam layer, it is also possible to three-dimensionally crosslink the area to which the foaming inhibitor is applied.

The means for applying heat energy is not particularly limited and can be appropriately selected depending on the purpose. Examples of the means include an infrared heater, a hot air heater, a heating roller, and the like.
The temperature at which heat energy is applied for heating is not particularly limited as long as the foam layer can be thermally cured, and can be appropriately selected depending on the purpose. The temperature is preferably equal to or higher than the thermal decomposition temperature of the foaming agent, for example, 100°C or higher and 200°C or lower.

When the energy is active energy rays, for example, the foam layer is cured by irradiating the foam layer with active energy rays.

- Active energy rays -
The active energy rays are not particularly limited, and may be any rays that can provide the energy required to promote the polymerization reaction of the polymerizable components in the composition, such as ultraviolet rays, electron beams, α rays, β rays, γ rays, and X-rays. In particular, when a high-energy light source is used, the polymerization reaction can be promoted without using a polymerization initiator. In addition, in the case of ultraviolet irradiation, mercury-free irradiation is strongly desired from the viewpoint of environmental protection, and replacement with a GaN-based semiconductor ultraviolet light-emitting device is very useful industrially and environmentally. Furthermore, ultraviolet light-emitting diodes (UV-LEDs) and ultraviolet laser diodes (UV-LDs) are small, have a long life, are highly efficient, and are low cost, and are therefore preferable as ultraviolet light sources.

The curing conditions are not particularly limited and can be appropriately selected depending on the purpose. In the case of ultraviolet light, it is preferable to use an irradiation device capable of irradiating with an intensity of 6 W/cm or more at an irradiation distance of 2 mm.
In the case of electron beams, the acceleration voltage is preferably set to a value that results in a dose of 15 kGy or more at the location farthest from the electron beam irradiation device where curing is desired.

The average thickness of the foam layer (before foaming) is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 50 μm or more, more preferably 100 μm or more, even more preferably 250 μm or more, and particularly preferably 300 μm or more and 500 μm or less.
When the average thickness of the foamed layer (before foaming) is 50 μm or more, a foamed layer having unevenness can be formed, and excellent designability due to the uneven shape can be imparted.
The average thickness of the foamed layer after foaming is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 100 μm or more, more preferably 310 μm or more, even more preferably 400 μm or more, and particularly preferably 400 μm or more and 2,000 μm or less.
When the average thickness after foaming is 100 μm or more, a foamed layer having unevenness due to the foaming inhibitor can be formed, and excellent designability due to the uneven shape can be imparted.
The average value of the average thickness can be obtained by scraping off the foam layer at five different points, measuring the height from the substrate to the surface of the foam layer at those points using, for example, a laser microscope VK-X100 manufactured by Keyence Corporation, and calculating the average value.

In addition, for the foamed layer of the present invention, the average thickness of the foamed region of the foamed layer after foaming is preferably at least 1.3 times, and more preferably at least 2 times, the average thickness before foaming. By doing so, a foamed layer with unevenness can be formed, and excellent design properties can be achieved through the uneven shape.

<Foaming Inhibitor Application Step, Foaming Inhibitor Application Means>
The foaming inhibitor application step is a step of applying a foaming inhibitor containing a polyfunctional monomer to a predetermined region of the foam layer to bring the foaming inhibitor into contact with the predetermined region.
The foaming inhibitor applying means is a means for applying a foaming inhibitor containing a polyfunctional monomer to a predetermined region of the foam layer to bring the foaming inhibitor into contact with the predetermined region.

The method of applying and contacting the foam inhibitor is not particularly limited and can be appropriately selected depending on the purpose, but the inkjet method is preferred because it can flexibly accommodate various foaming patterns (foaming inhibition patterns). In other words, in the foam inhibitor application step, the foam inhibitor is applied by the inkjet method, so that it can flexibly accommodate various foaming patterns (foaming inhibition patterns).
As an inkjet method, for example, the driving method for the ejection head can be an on-demand type head that uses a piezoelectric element actuator using PZT or the like, a method that uses thermal energy, an actuator that uses electrostatic force, or the like, or a continuous ejection type charge control type head can be used.
The amount of foam inhibitor to be applied is not particularly limited and can be appropriately selected depending on the purpose, but it is preferably 3 μL/cm ² or less relative to the surface of the foam layer.
The discharge speed of the foaming inhibitor is not particularly limited and can be appropriately selected depending on the purpose, and is preferably 5 m/s or more, and more preferably 5 m/s or more and 15 m/s or less. This allows the foaming inhibitor to be discharged more stably. The dot density (image resolution) of the discharged droplets of the foaming inhibitor is preferably 240 dpi x 240 dpi (dots per inch) or more.

The foam inhibitor contains a polyfunctional monomer and further contains other components as required.
The polyfunctional monomer may be the same as the polyfunctional monomer in the curable composition of the foam layer, and examples thereof include 1,6-hexanediol di(meth)acrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, diethylene glycol diacrylate, neopentyl glycol diacrylate, dipropylene glycol diacrylate, etc. Also, a mixture of different polyfunctional monomers, a mixture of a polyfunctional monomer and a monofunctional monomer, a mixture of an oligomer having a polyfunctionality and a monofunctional monomer, or a mixture of a monofunctional monomer, a polyfunctional monomer, and an oligomer having a polyfunctionality may be used.
Since polyfunctional monomers, for example, undergo three-dimensional crosslinking when energy is applied, by including a polyfunctional monomer in the foaming inhibitor, it is possible to precisely control foaming on and off (whether or not to foam in that area) by applying the foaming inhibitor to a specific area of the foam layer and then applying energy, which has the advantage of imparting excellent design features to the printed matter through the provision of an uneven shape.

The foaming inhibitor may contain other components such as a polymerization initiator and a surfactant, as in the foaming layer forming liquid.
The static surface tension of the foam inhibitor can be appropriately adjusted depending on the application and means of application, but is preferably 20 mN/m or more and 55 mN/m or less at 25°C.
The viscosity of the foam inhibitor can be appropriately adjusted depending on the application and means of application, but is preferably 1 mPa·s or more and 100 mPa·s or less at 25°C.

The specific area in the foam layer where the foam inhibitor is applied and brought into contact can be specified, for example, based on data on the unevenness of the printed matter to be produced. In the foam inhibitor application process, for example, the foam inhibitor is applied and brought into contact with a portion that is a recess (an area where the foam layer is not to be foamed) in the unevenness data of the printed matter to be produced, thereby suppressing the foaming of the foam layer in the foaming process and forming any uneven shape.

<Ink Receiving Layer Forming Step and Ink Receiving Layer Forming Means>
The ink receiving layer forming step is a step of forming an ink receiving layer containing a polymer of the polymerizable compound a on the foam layer.
The ink receiving layer forming means is a means for forming an ink receiving layer containing a polymer of the polymerizable compound a on the foam layer.
The ink receiving layer forming means is not particularly limited and can be appropriately selected depending on the purpose. For example, similar to the foam layer forming means, it can be a combination of a known material applying means (e.g., a coating means, a discharge means, etc.) and a known energy applying means (e.g., a thermal energy applying means, an active energy ray irradiation means, etc.).

The ink receiving layer forming step is not particularly limited as long as it can form an ink receiving layer, but for example, it is preferable to form the ink receiving layer by applying an ink receiving layer forming liquid containing a polymerizable compound a onto a substrate by a material applying means to form a film, and then curing the liquid by an energy applying means. In other words, in the ink receiving layer forming step, it is preferable to form the ink receiving layer by applying an ink receiving layer forming liquid containing a polymerizable compound a onto a foam layer, and then curing the ink receiving layer forming liquid.
Furthermore, the timing for curing the ink receiving layer forming liquid is not particularly limited and can be selected appropriately depending on the purpose. For example, when curing the ink that forms the foam layer or the image, the ink receiving layer and at least one of the foam layer and the ink that forms the image may be cured together, and it is preferable to cure the ink receiving layer and the ink that forms the image together.

<<Ink Receiving Layer Forming Liquid>>
The ink receiving layer forming liquid contains the polymerizable compound a, and preferably contains a polymerization initiator, and further contains other components as required.

--Polymerizable compound a--
As the polymerizable compound a, the same polymerizable solvent (polymerizable compound) as that of the foam layer forming liquid for the foam layer described above can be used.

- Polymerization initiator -
As the polymerization initiator, the same polymerization initiator as that in the foam layer forming liquid for the foam layer described above can be used.

-Other ingredients-
The other components in the ink receiving layer forming liquid are not particularly limited and may be appropriately selected depending on the purpose, and may be the same as the other components in the foaming layer forming liquid.

The static surface tension of the ink receiving layer forming liquid can be appropriately adjusted depending on the application and the means of application, but is preferably 15 mN/m or more and 50 mN/m or less at 25°C.
The viscosity of the ink receiving layer forming liquid can be adjusted appropriately depending on the application and the means of application, but is preferably 10 mPa·s or more and 20,000 mPa·s or less at 25°C.

The method for applying the ink receiving layer forming liquid onto the foam layer is not particularly limited and can be appropriately selected depending on the purpose. Examples include coating methods such as knife coating, nozzle coating, die coating, lip coating, comma coating, gravure coating, rotary screen coating, reverse roll coating, roll coating, spin coating, kneader coating, bar coating, blade coating, casting, dipping, curtain coating, and inkjet methods.

The amount of ink-receiving layer-forming liquid applied (average film thickness of the ink-receiving layer) is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 1 μm or more, and more preferably 2 μm to 50 μm. By having the average film thickness of the ink-receiving layer be 1 μm or more, better image quality can be obtained. The film thickness here refers to the film thickness after the ink-receiving layer-forming liquid is cured (after the ink-receiving layer is formed). The average value of the average film thickness can be obtained by observing the cross section of the coating film consisting of the foam layer and the ink-receiving layer under a microscope, measuring the thickness of the ink-receiving layer at five different points, and calculating the average value.

Here, the method for curing the ink receiving layer forming liquid is not particularly limited and can be selected appropriately depending on the purpose. For example, it can be performed by an energy application process, as in the case of the foamed layer.

When the energy is thermal energy, the color material layer can be cured by applying the thermal energy.
The temperature at which heat energy is applied for heating is not particularly limited as long as the color material layer can be thermally cured, and can be appropriately selected depending on the purpose.

When the energy is active energy rays, the color material layer can be cured by irradiation with the active energy rays.
The curing conditions are not particularly limited and can be appropriately selected depending on the purpose. In the case of ultraviolet light, it is preferable to use an irradiation device capable of irradiating with an intensity of 6 W/cm or more at an irradiation distance of 2 mm.
In the case of electron beams, the acceleration voltage is preferably set to a value that results in a dose of 15 kGy or more at the location farthest from the electron beam irradiation device where curing is desired.

<Image forming process, image forming means>
The image forming step is a step of forming an image by applying an ink containing a coloring material and a polymerizable compound b onto the ink receiving layer.
The image forming means is a means for forming an image by applying an ink containing a coloring material and a polymerizable compound b onto the ink receiving layer.
The image forming means is not particularly limited and can be appropriately selected depending on the purpose. For example, similar to the foam layer forming means, it can be a combination of a known material applying means (e.g., a coating means, a discharge means, etc.) and a known energy applying means (e.g., a thermal energy applying means, an active energy ray irradiation means, etc.).

The image forming step is not particularly limited as long as an image can be formed, but for example, it is preferable to form an image by applying an ink containing a coloring material and a polymerizable compound b onto the ink receiving layer by a material applying means to form a film, and then curing the ink by an energy applying means. In other words, in the image forming step, it is preferable to form an image by applying an ink onto the ink receiving layer and then curing the ink. This can further improve the durability of the image against external impacts and the like.
Furthermore, the timing of curing the ink is not particularly limited and can be selected appropriately depending on the purpose. For example, when curing the foam layer or the ink receiving layer, at least one of the foam layer and the ink receiving layer and the ink forming the image may be cured together, and it is preferable to cure the ink receiving layer and the ink forming the image together.
In other words, in the present invention, it is preferable to perform the curing of the ink-receiving layer forming liquid in the ink-receiving layer forming step and the curing of the ink in the image forming step together. By doing so, in the present invention, the ink-receiving layer and the image formed by the ink can be more integrated, and the color development of the image formed by the ink can be further improved, and the durability of the image against external impacts and the like can also be further improved.

The method of applying the ink onto the ink receiving layer is not particularly limited and can be appropriately selected depending on the purpose, but the inkjet method is preferred from the viewpoints of productivity and flexibility in handling small lots and a wide variety of products. In other words, in the present invention, by applying the ink onto the ink receiving layer by the inkjet method in the image forming process, productivity can be improved and flexibility in handling small lots and a wide variety of printed matter can be handled.
In the inkjet method, for example, the driving method for the ejection head can be an on-demand type head that uses a piezoelectric element actuator using PZT (lead zirconate titanate) or the like, a method that uses thermal energy, an actuator that uses electrostatic force, or the like, or a continuous ejection type charge control type head can be used.

The inks applied in the image forming process can be three, four, or more types of ink depending on the coloring material (pigment) contained in the ink, and for example, each type is applied by a separate inkjet head. Also, a head having a plurality of nozzle rows and ejecting different types of ink from each nozzle row may be used. It is preferable to change the head nozzle density for ejecting each ink according to the image resolution of the image formed in the image forming process and the number of scans of the head, and can be, for example, 240 npi (nozzles per inch), 300 npi, 600 npi, 1,200 npi, etc.
The amount of ink applied is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 3 μL/ ^cm2 or less on the surface of the ink receiving layer. By setting the amount of ink applied to the surface of the ink receiving layer to 3 μL/cm2 or ^less , unwanted coalescence of inks, color mixing of inks, and a decrease in color gamut can be further suppressed, and better image quality can be obtained.
The ink ejection speed is not particularly limited and can be appropriately selected depending on the purpose, and is preferably 5 m/s or more, and more preferably 5 m/s to 15 m/s. This allows the ink to be ejected more stably. The dot density (image resolution) of the ejected ink droplets is preferably 240 dpi x 240 dpi (dots per inch) or more.

Here, the shape of the image is not particularly limited and can be selected appropriately depending on the purpose. For example, an inkjet head can be used to eject ink based on the image data for the printed matter to be produced, forming any image (color material layer).

<<Ink>>
The ink contains a coloring material and a polymerizable compound b, and preferably contains a polymerization initiator, and further contains other components as necessary.

- Coloring materials -
As the coloring material, various pigments and dyes that impart glossy colors such as black, white, magenta, cyan, yellow, green, orange, purple, gold, silver, etc. can be used depending on the purpose and required characteristics of the ink in the present invention.
The content of the colorant may be appropriately determined taking into consideration the desired color density, dispersibility in the composition, and the like, and is not particularly limited. However, the content is preferably 0.1% by mass or more and 20% by mass or less, and more preferably 1% by mass or more and 10% by mass or less, relative to the total amount of the ink.
As the pigment, an inorganic pigment or an organic pigment can be used, and one type may be used alone, or two or more types may be used in combination.
Examples of inorganic pigments include carbon blacks (C.I. Pigment Black 7) such as furnace black, lamp black, acetylene black, and channel black, iron oxide, and titanium oxide.
Examples of organic pigments include azo pigments such as insoluble azo pigments, condensed azo pigments, azo lakes, and chelate azo pigments; polycyclic pigments such as phthalocyanine pigments, perylene and perinone pigments, anthraquinone pigments, quinacridone pigments, dioxane pigments, thioindigo pigments, isoindolinone pigments, and quinophthalone pigments; dye chelates (e.g., basic dye chelates, acid dye chelates, etc.); dye lakes (e.g., basic dye lakes, acid dye lakes, etc.); nitro pigments, nitroso pigments, aniline black, and daylight fluorescent pigments.
In order to improve the dispersibility of the pigment, a dispersant may be further contained.
The dispersant is not particularly limited, but examples thereof include dispersants commonly used in preparing pigment dispersions, such as polymer dispersants.
As the dye, for example, acid dyes, direct dyes, reactive dyes, and basic dyes can be used, and one type of dye may be used alone, or two or more types may be used in combination.

--Polymerizable compound b--
The polymerizable compound b can be the same as the polymerizable solvent (polymerizable compound) in the foam layer forming liquid in the foam layer described above. The polymerizable compound b in the ink receiving layer forming liquid is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 70% by mass or more and 95% by mass or less with respect to the total amount of the ink.

- Polymerization initiator -
As the polymerization initiator, the same polymerization initiator as that in the foam layer forming liquid for the foam layer described above can be used.

The ink may further contain a dispersant to improve the dispersibility of the pigment. The dispersant is not particularly limited, but examples thereof include dispersants commonly used to prepare pigment dispersions, such as polymer dispersants.

-Other ingredients-
The other components in the ink are not particularly limited and can be appropriately selected depending on the purpose. Examples of the other components include organic solvents, surfactants, polymerization inhibitors, leveling agents, defoamers, fluorescent brightening agents, penetration promoters, wetting agents (moisturizing agents), fixing agents, viscosity stabilizers, antifungal agents, preservatives, antioxidants, ultraviolet absorbers, chelating agents, pH adjusters, and thickeners.

--Organic solvent--
The ink of the present invention may contain an organic solvent, but preferably does not contain an organic solvent if possible. If the composition does not contain an organic solvent, particularly a volatile organic solvent (VOC (Volatile Organic Compounds)-free), the safety of the place where the composition is handled is improved and it is possible to prevent environmental pollution. Note that the "organic solvent" means a general non-reactive organic solvent such as ether, ketone, xylene, ethyl acetate, cyclohexanone, toluene, etc., and should be distinguished from a reactive monomer. In addition, "not containing" an organic solvent means that the organic solvent is substantially not contained, and it is preferable that the organic solvent content is less than 0.1 mass %.

- Preparation of colorant composition -
The ink used in the present invention can be prepared using the various components described above. There are no particular limitations on the preparation means or conditions. For example, the ink can be prepared by putting a pigment as a colorant, a dispersant, etc. into a dispersing machine such as a ball mill, a Kitty mill, a disk mill, a pin mill, or a Dyno mill, dispersing the pigment, preparing a pigment dispersion, and further mixing a polymerizable compound, a polymerization initiator, a polymerization inhibitor, a surfactant, etc. into the pigment dispersion.

The viscosity of the ink used in the present invention may be appropriately adjusted depending on the application and application means, and is not particularly limited. For example, when applying an ejection means for ejecting the composition from a nozzle, the viscosity in the range of 20°C to 65°C, desirably the viscosity at 25°C is preferably 3 mPa·s to 40 mPa·s, more preferably 5 mPa·s to 15 mPa·s, and particularly preferably 6 mPa·s to 12 mPa·s. It is particularly preferable that the viscosity range is satisfied without containing the organic solvent. The viscosity can be measured by using a cone-plate type rotational viscometer VISCOMETER TVE-22L manufactured by Toki Sangyo Co., Ltd., using a cone rotor (1°34'×R24), at a rotation speed of 50 rpm, and by appropriately setting the temperature of the constant temperature circulating water in the range of 20°C to 65°C. A VISCOMATE VM-150III can be used to adjust the temperature of the circulating water.
The static surface tension of the ink can be adjusted appropriately depending on the application and means of application, but is preferably 20 mN/m or more and 55 mN/m or less at 25°C.

Here, the method for curing the ink is not particularly limited and can be selected appropriately depending on the purpose. For example, it can be performed by an energy application process, as in the case of the foam layer.

When the energy is thermal energy, the color material layer can be cured by applying the thermal energy.
The temperature at which heat energy is applied for heating is not particularly limited as long as the color material layer can be thermally cured, and can be appropriately selected depending on the purpose.

When the energy is active energy rays, the color material layer can be cured by irradiation with the active energy rays.
The curing conditions are not particularly limited and can be appropriately selected depending on the purpose. In the case of ultraviolet light, it is preferable to use an irradiation device capable of irradiating with an intensity of 6 W/cm or more at an irradiation distance of 2 mm.
In the case of electron beams, the acceleration voltage is preferably set to a value that results in a dose of 15 kGy or more at the location farthest from the electron beam irradiation device where curing is desired.

<Foaming process, foaming means>
The foaming step is a step in which the foam layer is heated to foam (expand in volume).
The foaming means is a means for heating the foam layer to foam (expand the volume).
The foaming means is not particularly limited as long as it is capable of foaming the foaming agent in the foam layer by heating, and can be appropriately selected depending on the purpose. Examples of the foaming means include an infrared heater, a hot air heater, and a heating roller.
The temperature at which the mixture is heated in the heating step is not particularly limited as long as it is equal to or higher than the thermal decomposition temperature of the foaming agent, and may be appropriately selected depending on the purpose. For example, a temperature of 100° C. or higher and 200° C. or lower is preferable.

The timing of the foaming step is not particularly limited as long as it is after the foaming layer forming step, and can be appropriately selected according to the purpose. More specifically, for example, as described above, when the foaming layer forming liquid is hardened by applying thermal energy in the foaming layer forming step, the foaming step may be performed all at once, or the foaming step may be performed after the foaming layer forming liquid is hardened. Furthermore, in the present invention, the foaming step may be performed after the ink receiving layer forming step and before the image forming step, or after the formation of each layer (e.g., foaming layer, ink receiving layer) and image is completed (after the image forming step).
In the present invention, it is preferable to carry out the foaming step after the image forming step. In this way, in the present invention, the ink receiving layer forming step and the image forming step are carried out on a foamed layer in an unfoamed state (a flat foamed layer without unevenness), so that when an image is formed by ejecting ink from an inkjet head or the like, the ink can be stably landed on the ink receiving layer, and the color development of the formed image can be further improved.

In addition, when foaming the foam layer, the method of forming the foamed and non-foamed regions is not limited to the application of a foaming inhibitor described below, but can be appropriately selected depending on the purpose. The foamed and non-foamed regions in the foam layer can be formed, for example, by selectively heating the foamed regions in the foam layer. In this case, for example, a laser irradiation means can be used as the foaming means.

<Transparent Layer Forming Step and Transparent Layer Forming Means>
The transparent layer forming step is a step of forming a transparent layer containing a polymer of the polymerizable compound c on at least one of the ink receiving layer and the image.
The transparent layer forming means is a means for forming a transparent layer containing a polymer of the polymerizable compound c on at least one of the ink receiving layer and the image.
In the present invention, by including the transparent layer forming step, the durability of the formed uneven shape and image can be further improved, and the excellent design and image quality due to the uneven shape can be maintained for a long period of time.
The transparent layer forming means is not particularly limited and can be appropriately selected depending on the purpose. For example, similar to the foamed layer forming means, it can be a combination of a known material applying means (e.g., a coating means, a discharging means, etc.) and a known energy applying means (e.g., a thermal energy applying means, an active energy ray irradiation means, etc.).

In the present invention, a transparent layer means a layer whose haze (scattered light/total light transmission x 100 (%)) measured by performing an optical property test using a haze-gard i (haze meter, manufactured by BYK) is 8% or less.

In the present invention, the transparent layer forming step is performed after the ink receiving layer forming step or after the image forming step. In this way, the transparent layer can be formed on at least one of the ink receiving layer and the image. That is, in the present invention, the transparent layer may be formed between the ink receiving layer and the image, or may be formed on the ink receiving layer and the image. In addition, when an image (solid image) is formed on the entire surface of the ink receiving layer, the ink layer may be formed only on the image.
In the present invention, it is preferable to form a transparent layer at least on the image in the transparent layer forming step. In other words, in the present invention, it is preferable to perform the transparent layer forming step after the image forming step, and form a transparent layer on the image. By doing so, in the present invention, it is possible to particularly improve the durability of the formed uneven shape and image, and further to maintain the design and image quality due to the excellent uneven shape for a long period of time.

In the transparent layer forming process, for example, a transparent layer forming liquid (clear ink) containing polymerizable compound c is applied by a material application means to form a film, and then the film is cured by an energy application means to form a transparent layer. In other words, in the transparent layer forming process, for example, a film containing polymerizable compound c is produced, and the film is cured to form a transparent layer containing a polymer of the polymerizable compound c.

The transparent layer forming liquid (clear ink) contains a polymerizable compound c, and preferably contains a polymerization initiator, and further contains other components as necessary.

--Polymerizable compound c--
As the polymerizable compound c, the same polymerizable solvent (polymerizable compound) as that of the foam layer forming liquid in the foam layer described above can be used. In the present invention, the polymerizable compound a, the polymerizable compound b, and the polymerizable compound c may be the same polymerizable compound or different polymerizable compounds.

- Polymerization initiator -
As the polymerization initiator, the same polymerization initiator as that in the foam layer forming liquid for the foam layer described above can be used.

-Other ingredients-
The other components in the transparent layer forming liquid are not particularly limited and may be appropriately selected depending on the purpose, and may be the same as the other components in the foam layer forming liquid.

In addition, as the transparent layer forming liquid (clear ink), for example, an ink that does not contain a coloring material can be used in the image forming process. Incidentally, "not containing a coloring material" means that the coloring material is substantially not contained, and the content of the coloring material is preferably less than 0.1% by mass.
Here, from the viewpoint of maintaining the excellent design and image quality due to the uneven shape for a longer period of time by forming a transparent layer, it is preferable that the transparent layer forming liquid (clear ink) used in the image forming process does not contain a colorant and further has a high content of polyfunctional monomer/oligomer in the polymerizable compound b.
The static surface tension of the transparent layer forming liquid (clear ink) can be adjusted appropriately depending on the application and means of application, but is preferably 20 mN/m or more and 55 mN/m or less at 25°C.
The viscosity of the transparent layer forming liquid (clear ink) can be adjusted appropriately depending on the application and means of application, but is preferably 1 mPa·s or more and 100 mPa·s or less at 25° C. When the transparent layer forming liquid (clear ink) is applied by an inkjet method, the viscosity is preferably 5 mPa·s or more and 20 mPa·s or less.

The method of applying the transparent layer forming liquid (clear ink) onto at least one of the ink receiving layer and the image is not particularly limited and can be appropriately selected depending on the purpose, but the inkjet method is preferred because it allows the transparent layer forming liquid (clear ink) to be applied without contacting the ink receiving layer or the image.
The amount of the transparent layer forming liquid (clear ink) to be applied is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 3 μL/cm ² or less relative to the surface of the ink receiving layer.
The ejection speed of the transparent layer forming liquid (clear ink) is not particularly limited and can be appropriately selected depending on the purpose, and is preferably 5 m/s or more, and more preferably 5 m/s or more and 15 m/s or less. This allows the transparent layer forming liquid (clear ink) to be ejected more stably.

<Substrate surface modification step, substrate surface modification means>
The substrate surface modification step is a step of modifying the surface of the substrate on which the foam layer is to be formed by subjecting the substrate to a corona discharge treatment.
The substrate surface modification means is a means for modifying the surface of the substrate on which the foam layer is formed by subjecting the substrate to a corona discharge treatment.
The surface modification means for the substrate is not particularly limited as long as it can perform corona discharge treatment on the substrate, and can be appropriately selected depending on the purpose, and a known corona discharge treatment device can be used. For example, TEC-4AX (manufactured by Kasuga Electric Co., Ltd.) can be used as the corona discharge treatment device.

In the present invention, the substrate surface modification step is carried out before the foam layer formation step. In other words, in the present invention, it is preferable to carry out a substrate surface modification step in which the substrate on which the foam layer is to be formed is subjected to a corona discharge treatment to modify the surface before the foam layer formation step. By doing so, in the present invention, the wettability and adhesion of the foam layer forming liquid to the substrate can be improved, and the adhesion between the foam layer and the substrate after curing and foaming is improved, thereby further improving the durability of the image against external impacts, etc.

In the substrate surface modification process, the substrate surface can be modified by performing corona discharge treatment using, for example, the above-mentioned TEC-4AX (manufactured by Kasuga Electric Co., Ltd.) with an electrode-substrate surface gap of 1 mm, 2 m/min, and 100 W.

<Foam layer surface modification step, foam layer surface modification means>
The foam layer surface modification step is a step of modifying the surface of the foam layer by subjecting the foam layer to a corona discharge treatment.
The foam layer surface modification means is a means for modifying the surface of the foam layer by subjecting the foam layer to a corona discharge treatment.
The foam layer surface modification means is not particularly limited as long as it can perform a corona discharge treatment on the foam layer, and can be appropriately selected depending on the purpose. As with the substrate surface modification means, a known corona discharge treatment device can be used. As with the substrate surface modification means, for example, a TEC-4AX (manufactured by Kasuga Electric Co., Ltd.) can be used as the corona discharge treatment device.

In the present invention, the foam layer surface modification step is performed after the foam layer formation step. In other words, in the present invention, it is preferable to perform a foam layer surface modification step in which the foam layer is subjected to a corona discharge treatment to modify the surface after the foam layer formation step. By doing so, in the present invention, the wettability and adhesion of the ink normal layer forming liquid to the foam layer can be improved, and the adhesion between the ink receiving layer and the foam layer after curing and foaming can be improved, thereby further improving the durability of the image against external impacts, etc.

In the foam layer surface modification process, the foam layer can be surface modified by performing corona discharge treatment using, for example, the above-mentioned TEC-4AX (manufactured by Kasuga Electric Co., Ltd.) with an electrode-substrate surface gap of 1 mm, 2 m/min, and 100 W.

<Filler-Containing Layer Forming Step and Filler-Containing Layer Forming Means>
The filler-containing layer forming step is a step of forming a filler-containing layer containing a filler on at least one of the ink receiving layer and the image.
The filler-containing layer forming means is a means for forming a filler-containing layer containing a filler on at least one of the ink receiving layer and the image.
By providing a filler-containing layer containing a filler on at least one of the ink receiving layer and the image, it is possible to obtain a printed matter having improved robustness such as abrasion resistance while maintaining high designability due to the uneven shape and improving the strength of the foam layer.
The filler-containing layer forming means is not particularly limited and can be appropriately selected depending on the purpose. For example, similar to the foamed layer forming means, it can be a combination of a known material applying means (e.g., a coating means, a discharge means, etc.) and a known energy applying means (e.g., a thermal energy applying means, an active energy ray irradiation means, etc.).

In the filler-containing layer forming process, for example, a filler-containing layer forming liquid containing a filler and a polymerizable compound d is applied by a material application means onto at least one of the ink receiving layer and the image to form a film, and then cured by an energy application means to form the filler-containing layer. In other words, in the present invention, for example, in the filler-containing layer forming process, a filler-containing layer forming liquid containing a filler and a polymerizable compound d is applied onto at least one of the ink receiving layer and the image, and then the filler-containing layer forming liquid is cured to form the filler-containing layer.

<<Filler-containing layer forming liquid>>
The filler-containing layer forming liquid contains a filler and preferably contains a polymerizable compound, and further contains other components as necessary.

-Filler-
There are no particular limitations on the filler, so long as it improves the fastness of the printed matter, such as abrasion resistance and scratch resistance, and has high light transmittance, and the filler can be appropriately selected depending on the purpose.

The filler preferably has a refractive index of 1.46 or more and 1.58 or less. When the refractive index of the filler is 1.46 or more and 1.58 or less, a highly transparent filler-containing layer can be formed because the refractive index of common olefins and acrylic resins is approximately in this range. That is, when the refractive index of the filler is 1.46 or more and 1.58 or less, the difference in refractive index between the polymerizable compound and the filler can be reduced, the scattering of the filler can be reduced, the light transmittance of the image can be improved, and a printed matter in which the non-uniformity of the image density and the decrease in image resolution are suppressed can be provided.
The refractive index of the filler can be measured, for example, by dispersing the filler in an acrylic polymerizable compound to prepare a filler liquid, forming a film of this on a silicon wafer by spin coating, and using the film as a sample for refractive index measurement, and then measuring the refractive index using a commercially available spectroscopic ellipsometer.
The filler may be, for example, an inorganic filler.

The material of the inorganic filler is not particularly limited and can be appropriately selected depending on the purpose, and is preferably, for example, glass, silica, alumina, etc. These may be used alone or in combination of two or more kinds.
Among these, glass is preferred as the material of the inorganic filler. When the material of the inorganic filler is glass, various physical properties can be easily controlled by simply adjusting the composition of the glass. Since fused silica (refractive index 1.46), crystalline silica (refractive index 1.55), and aluminum hydroxide (refractive index 1.58), which are generally used as fillers, have refractive indices specific to the material, it is necessary to adjust the refractive index of the filler-containing liquid in order to obtain transparency. However, for example, when the filler-containing liquid contains an acrylic ultraviolet-curable resin as a polymerizable compound, it is possible to easily match the refractive index of the resin consisting of the filler and the polymerizable compound by taking advantage of the degree of freedom of refractive index adjustment, which is a feature of the glass filler, and thus the light transmittance (transparency) of the filler-containing layer can be controlled.

Examples of glass include non-alkali silicate glass such as E glass, alkali-containing silicate glass such as C glass, and ordinary soda-lime glass. These may be used alone or in combination of two or more types.

It is preferable that the filler is surface-treated to disperse in the resin. Commercially available products such as the Filatomicta series manufactured by Nippon Muki Co., Ltd. can be used as such fillers.

The shape of the filler is not particularly limited and can be appropriately selected depending on the purpose. For example, the filler may be in the form of flakes, fibers, powder, beads, or the like.
The structure of the filler is not particularly limited and can be appropriately selected depending on the purpose.

Regarding the size of the filler, when the shape is spherical or nearly spherical, or when the fibrous filler is spherical, the average primary particle size of the filler is preferably 0.1 μm or more and 1.0 μm or less. When the average primary particle size of the filler is 0.1 μm or more and 1.0 μm or less, the settling of the filler in the filler-containing layer forming liquid can be suppressed and good dispersibility can be obtained. Even if the primary particles aggregate, the maximum size can be approximately 5 μm or less, so that adhesion with the foam layer can be maintained and the abrasion resistance of the printed matter can be improved.

The method for measuring the average primary particle size is not particularly limited and can be appropriately selected depending on the purpose. For example, a laser diffraction/scattering type particle size distribution measuring device MT3000II (manufactured by Microtrack Bell Co., Ltd.) can be used to measure the particle size.
The method for measuring the average primary particle size of the filler contained in the filler-containing layer of the printed material is not particularly limited and can be appropriately selected depending on the purpose. For example, the printed material is sampled, stirred in chloroform, and then the diameter of the filler is observed and measured using an electron microscope to confirm the average primary particle size of the filler.

In addition, when the filler has a fibrous shape, it is preferable that the average length of the long side is 0.6 μm or more and 5 μm or less.

The filler content in the filler-containing layer forming liquid is preferably 0.1% by mass or more and 20% by mass or less, and more preferably 0.1% by mass or more and 10% by mass or less. When the filler content in the filler-containing layer forming liquid is 0.1% by mass or more and 20% by mass or less, the abrasion resistance of the printed matter is improved, and the adhesion with the foam layer is also improved, so that a printed matter with good image quality can be obtained.

--Polymerizable compound d--
As the polymerizable compound d, the same polymerizable solvent (polymerizable compound) as that of the foam layer forming liquid in the foam layer described above can be used. In the present invention, the polymerizable compound a, the polymerizable compound b, the polymerizable compound c, and the polymerizable compound d may be the same polymerizable compound or different polymerizable compounds.
The content of the polyfunctional monomer and polyfunctional oligomer in the filler-containing layer forming liquid is preferably 50% by mass or more based on the total amount of the polymerizable compounds in the filler-containing layer forming liquid. When the content of the polyfunctional monomer and polyfunctional oligomer in the filler-containing layer forming liquid is 50% by mass or more based on the total amount of the polymerizable compounds in the filler-containing layer forming liquid, the abrasion resistance and scratch resistance of the printed surface can be improved.

-Other ingredients-
Examples of other components include a polymerization initiator, a filler, a volume expansion promoter, a dispersant, a coloring material, an organic solvent, an antiblocking agent, a thickener, a preservative, a stabilizer, a deodorizer, a fluorescent agent, an ultraviolet blocking agent, etc. These can be the same as those used in the foam layer forming liquid.
In order to adjust the static surface tension of the filler-containing layer forming liquid, a surfactant may be contained.

<Adhesive Layer Forming Step, Adhesive Layer Forming Means>
The adhesive layer forming step is a step of forming an adhesive layer on a substrate, which bonds the substrate and the foam layer, prior to the foam layer forming step.
The adhesive layer forming means is a means for forming an adhesive layer on the substrate to bond the substrate and the foam layer before the foam layer forming means forms the foam layer.
By providing an adhesive layer, it is possible to obtain a printed matter having excellent durability, which maintains the excellent design and image quality due to the excellent uneven shape for a long period of time.
The adhesive layer forming means is not particularly limited and can be appropriately selected depending on the purpose. For example, similar to the foam layer forming means, it can be a combination of a known material applying means (e.g., a coating means, a discharge means, etc.) and a known energy applying means (e.g., a thermal energy applying means, an active energy ray irradiation means, etc.).

In the adhesive layer forming process, for example, an adhesive layer forming liquid is applied to a substrate by a material applying means to form a film, and then the liquid is cured by an energy applying means to form an adhesive layer. In other words, in the adhesive layer forming process, for example, in the present invention, an adhesive layer forming liquid for forming an adhesive layer is applied to a substrate by a material applying means, and then the adhesive layer forming liquid is cured to form an adhesive layer.

<<Adhesive layer>>
The adhesive layer is not particularly limited as long as it can maintain the adhesion (adhesion) between the substrate and the foam layer when the foam layer is foamed (volume expanded), and can be appropriately selected depending on the purpose.
Here, the structure of the adhesive layer is not particularly limited as long as it can be provided between the substrate and the foam layer, and can be appropriately selected depending on the purpose. It may be a single-layer (one layer) structure or a multi-layer (multiple layers) structure.
For example, when the adhesive layer has a multi-layer structure, other layers or structures may be provided between the adhesive layers as long as the adhesiveness (adhesion) between the substrate and the foam layer can be maintained. Thus, the adhesive layer may directly bond the substrate and the foam layer, or indirectly bond the substrate and the foam layer.
In the following description, the adhesive layer may be referred to as an "intermediate layer" since it is provided between the substrate and the foam layer.

--Adhesive layer forming liquid--
The adhesive layer forming liquid contains, for example, at least one of a polymerizable compound e, a dispersion type resin, and a dissolution type resin, and preferably further contains solid fine particles, and further contains other materials as necessary. These may be used alone or in combination of two or more.
Thus, in the adhesive layer forming process, for example, an adhesive layer forming liquid for forming an adhesive layer is applied onto a substrate, and then the adhesive layer forming liquid is hardened to form an adhesive layer, and the adhesive layer forming liquid contains at least one of a polymerizable compound e, a dispersion type resin, and a soluble type resin.

As the polymerizable compound e, the same polymerizable solvent (polymerizable compound) as that of the foam layer forming liquid in the foam layer described above can be used. In the present invention, the polymerizable compound a, the polymerizable compound b, the polymerizable compound c, the polymerizable compound d, and the polymerizable compound e may be the same polymerizable compound or different polymerizable compounds.
Examples of the polymerizable compound e include polymerizable compounds that can give polymers with low glass transition points, polymerizable compounds having functional groups such as hydroxyl groups, carboxyl groups, epoxy groups, sulfo groups, and phospho groups at the molecular terminals, etc. These may be used alone or in combination of two or more.

Examples of polymerizable compounds that can give a polymer with a low glass transition point include polyethylene glycol (600) diacrylate (Tg: -42°C) as a compound containing an ethylene oxide skeleton, and tridecyl acrylate (Tg: -55°C) and isodecyl acrylate (Tg: -60°C) as compounds containing a linear alkyl chain. When the polymerizable compound e gives a polymer with a low glass transition point, the flexibility of the obtained adhesive layer can be improved, and the adhesion between the foamed layer and the substrate can be improved, thereby improving the durability of the obtained printed matter.
Examples of polymerizable compounds having a functional group such as a hydroxyl group, a carboxyl group, an epoxy group, a sulfo group, or a phospho group at the molecular end include 1,4-cyclohexanedimethanol monoacrylate, 2-acryloyloxyethyl succinate, 4-hydroxybutyl acrylate glycidyl ether, 2-acrylamido-2-methylpropanesulfonic acid, and 2-hydroxyethyl methacrylate acid phosphate.
The content of the polymerizable compound e relative to the total amount of the adhesive layer forming liquid is preferably from 1% by mass to 99% by mass, and more preferably from 10% by mass to 95% by mass.

The dispersion type resin is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include acrylic resins, vinyl acetate resins, styrene-butadiene resins, vinyl chloride resins, acrylic-styrene resins, butadiene resins, styrene resins, epoxy resins, etc. These may be used alone or in combination of two or more.
The particle size of the resin component in the dispersion resin is not particularly limited as long as it forms an emulsion, but is preferably 150 nm or less, and more preferably 5 nm or more and 100 nm or less. As the dispersion resin, a commercially available product can be used, and examples of the commercially available product include Boncoat W-26 (manufactured by DIC Corporation) and Boncoat W-386 (manufactured by DIC Corporation). These may be used alone or in combination of two or more types.
The content of the solid content of the dispersion-type resin relative to the total amount of the adhesive layer forming liquid is preferably from 1% by mass to 99% by mass, and more preferably from 10% by mass to 95% by mass.

The soluble resin (solvent-based resin) is not particularly limited as long as it is a resin dissolved in a solvent, and can be appropriately selected according to the purpose. For example, a resin such as an acrylic resin or a urethane resin dissolved in a solvent such as methyl ethyl ketone, dioxane, hexane, ethyl acetate, or butyl acetate can be mentioned. As the soluble resin, a commercially available product can be used. Examples of the commercially available product include Finetack CT-3088, Finetack CT-3850, Finetack CT-5020, Finetack CT-5030, Finetack CT-6030, Quickmaster SPS-900-LV, Quickmaster SPS-945NT, and Quickmaster SPS-1040NT-25 (all manufactured by DIC Corporation). These may be used alone or in combination of two or more types.
The content of the soluble resin in the total amount of the adhesive layer forming liquid is preferably from 1% by mass to 99% by mass, and more preferably from 10% by mass to 95% by mass.

The solid fine particles are different from the above-mentioned dispersion type resin, and are not particularly limited as long as they can improve the wettability of the substrate and suppress the deformation of the adhesive layer, and can be appropriately selected according to the purpose. For example, the solid fine particles include solid fine particles having hydroxyl groups on their surface. If the solid fine particles have hydroxyl groups on their surface, they can improve the wettability of the substrate surface and suppress the deformation of the adhesive layer, thereby improving the adhesion (adhesion) between the substrate and the foamed foam layer.
As the solid fine particles, commercially available products can be used, and examples of commercially available products include organosilica sol MA-ST-M, IPA-ST, and MEK-ST-UP (manufactured by Nissan Chemical Industries, Ltd.) These may be used alone or in combination of two or more kinds.
The content of the solid content of the solid fine particles relative to the total amount of the adhesive layer forming liquid is preferably from 1% by mass to 50% by mass, and more preferably from 5% by mass to 30% by mass.

The average thickness (amount applied) of the adhesive layer is not particularly limited and can be selected appropriately depending on the purpose. For example, 5 μm or more is preferable. If the average thickness (amount applied) of the adhesive layer is 5 μm or more, the adhesion between the substrate and the foam layer can be further improved. The average thickness is the thickness after curing and drying. The average value of the average thickness (amount applied) of the adhesive layer can be obtained by scraping off the intermediate layer at five different points, measuring the height from the substrate to the intermediate layer surface at those points using, for example, a Keyence VK-X100 laser microscope, and calculating the average value.

The method for forming the adhesive layer on the substrate is not particularly limited and can be appropriately selected according to the purpose. For example, coating methods such as knife coating, nozzle coating, die coating, lip coating, comma coating, gravure coating, rotary screen coating, reverse roll coating, roll coating, spin coating, kneader coating, bar coating, blade coating, casting, dipping, curtain coating, and inkjet methods can be mentioned.
In addition, it is preferable to subject the substrate to a surface treatment such as a corona treatment before forming the adhesive layer, in order to improve the coating uniformity and adhesion of the adhesive layer.

<Other steps and other means>
The other steps are not particularly limited and can be appropriately selected depending on the purpose. Examples of the other steps include a protective layer forming step of forming a protective layer different from the transparent layer, an embossing step, a bending step, a cutting step, and a control step.
The other means are not particularly limited and can be appropriately selected depending on the purpose. Examples of the other means include a protective layer forming means for forming a protective layer different from the transparent layer, an embossing means, a bending means, a cutting means, a control means, and the like.

<<Embossing process, embossing means>>
The embossing process is a process for forming a raised and recessed pattern on a printed material.
The embossing process is a process for forming a relief pattern on a printed matter.
In the embossing step, a method such as embossing, chemical embossing, rotary screen processing, or raised printing, which is generally used for the purpose of imparting unevenness to wallpaper, decorative materials, etc., can be appropriately selected and used.

Examples of the embossing means include a means for embossing with a heated and then cooled roller, and a means for embossing all at once using a heated roller embosser.
The depth of the embossing by the embossing process is preferably 0.08 mm or more and 0.50 mm or less. When the embossing depth is 0.08 mm or more, a three-dimensional effect can be created, and when it is 0.50 mm or less, the abrasion resistance of the surface can be improved.
Examples of the shape of the uneven pattern formed by embossing include vascular grooves of a wood grain plate, unevenness on the surface of a stone slab, texture on the surface of a cloth, matte finish, sand grain, hairline, and striped grooves.

<Printed materials>
The printed matter of the present invention comprises a bubble-containing layer which contains bubbles, an ink-receiving layer which is located on the bubble-containing layer and contains polymer A, and an image which is located on the ink-receiving layer and is formed from a cured product of an ink which contains a colorant and polymer B. It is preferable that the printed matter also comprises a transparent layer, and further comprises other layers as necessary.
The printed matter of the present invention can be suitably produced by the method and apparatus for producing a printed matter of the present invention. A preferred form of the printed matter of the present invention can be the same as a preferred form of the printed matter in the method for producing a printed matter of the present invention.

<<Bubble-containing layer>>
The bubble-containing layer is not particularly limited as long as it is a layer containing bubbles and can be appropriately selected depending on the purpose, but it is preferably a layer containing a foamed foaming agent. The bubble-containing layer is preferably, for example, a layer containing a porous portion.
In other words, the bubble-containing layer in the printed matter of the present invention can be suitably formed by the foam layer forming step and the foaming step in the method for producing a printed matter of the present invention. Therefore, the preferred form of the bubble-containing layer in the printed matter of the present invention can be the same as the preferred form of the foam layer in the method for producing a printed matter of the present invention.

<<Ink Receiving Layer>>
The ink-receiving layer is located on the bubble-containing layer and comprises Polymer A.
The ink-receiving layer in the printed matter of the present invention can be suitably formed by the ink-receiving layer forming step in the method for producing a printed matter of the present invention. Therefore, the preferred form of the ink-receiving layer in the printed matter of the present invention can be the same as the preferred form of the ink-receiving layer in the method for producing a printed matter of the present invention.

Here, the polymer A contained in the ink receiving layer in the printed matter of the present invention is not particularly limited as long as it is a polymer, and can be appropriately selected depending on the purpose. For example, it can be a polymer of the polymerizable compound a described above.

＜＜Images＞＞
The image in the printed matter of the present invention is located on the ink-receiving layer and is formed from a cured product of the ink containing a coloring material and polymer B.
The image in the printed matter of the present invention can be suitably formed by the image forming step in the method for producing a printed matter of the present invention. Therefore, the preferred form of the image in the printed matter of the present invention can be the same as the preferred form of the image in the method for producing a printed matter of the present invention.

Here, the ink contained in the image in the printed matter of the present invention may be, for example, the same as the ink used in the image forming process described above. In addition, the polymer B contained in the ink that forms the image in the printed matter of the present invention is not particularly limited as long as it is a polymer, and can be appropriately selected depending on the purpose, and can be, for example, a polymer of the polymerizable compound b described above.

<<Transparent layer>>
The printed matter of the present invention preferably has a transparent layer located on at least one of the ink-receiving layer and the image.
The transparent layer in the printed matter of the present invention can be suitably formed by the transparent layer forming step in the method for producing a printed matter of the present invention. Therefore, the preferred form of the transparent layer in the printed matter of the present invention can be the same as the preferred form of the transparent layer in the method for producing a printed matter of the present invention.

<<Other layers>>
The other layers in the printed matter of the present invention are not particularly limited and can be appropriately selected depending on the purpose.

Here, the printing material manufacturing apparatus of the present invention used in the printing material manufacturing method of the present invention will be described in detail with reference to the drawings.

Figure 1 is a schematic diagram showing an example of a printing production apparatus of the present invention. The printing production apparatus 100 in Figure 1 has an application roller 10 that applies the foam layer forming liquid onto a substrate 19, a foam inhibitor head 11 downstream of the application roller 10, a discharge head 16 having a black head 12, a cyan head 13, a magenta head 14, and a yellow head 15, active energy ray irradiation devices 17 and 27, a heating device 18, and an application roller 28 that applies the ink receiving layer forming liquid onto the substrate 19 to which the foam layer forming liquid has been applied. In Figure 1, 20 is a conveyor belt, 21 is a delivery roller that faces the application roller 10, and 22 is a take-up roller.

The substrate 19 is transported in the direction of the arrow in FIG. 1 by the transport belt 20 being wound by the winding roller 22 .
First, the foam layer forming liquid is applied to the surface of the substrate 19 by the application roller 10, and the substrate 19 to which the foam layer forming liquid has been applied is irradiated with active energy rays under predetermined irradiation conditions using the active energy ray irradiation device 27 to harden the foam layer forming liquid and form a foam layer. That is, in this example, the application roller 10 and the active energy ray irradiation device 27 are an example of a foam layer forming means.

Next, the substrate 19 is scanned at a predetermined speed, and the foaming inhibitor is ejected from the foaming inhibitor head 11 onto a predetermined area of the foam layer, contacting the foam layer. In other words, in this example, the foaming inhibitor head 11 is an example of a foaming inhibitor application means. Note that the predetermined area of the foam layer to which the foaming inhibitor is applied can be identified from data on the unevenness of the printed matter to be manufactured, as described above.

Next, the ink receiving layer forming liquid is applied onto the foam layer by a coating roller 28 .
Next, black, cyan, magenta, and yellow inks are ejected by an inkjet method from the heads for each color, namely, the black head 12, the cyan head 13, the magenta head 14, and the yellow head 15. Next, the base material 19 on which the ink has been applied is irradiated with active energy rays under predetermined irradiation conditions using the active energy ray irradiation device 17, and the ink receiving layer forming liquid and the ink are cured to form an ink receiving layer and an image. That is, in this example, the application roller 28 and the active energy ray irradiation device 17 are an example of an ink receiving layer forming means, and the ejection head 16 and the active energy ray irradiation device 17 are an example of an image forming means.
Next, the formed foam layer is expanded by heating it with the heating device 18. That is, in this example, the heating device 18 is an example of a foaming means.

In this way, the printed matter produced by the printed matter production device 100 has excellent design and image quality due to the uneven shape, and can maintain the excellent design and image quality due to the uneven shape for a long period of time.

In addition, FIG. 1 shows a case where the printed matter production device 100 is a single-pass type in which the width that can be printed by the inkjet head is larger than the width of the substrate to be printed and the number of scans is one. However, the printed matter production device of the present invention may be a multi-pass type in which the width of the head is smaller than the width of the substrate and a drive mechanism (head unit or substrate transport) is provided that allows multiple scans.

FIG. 2 is a schematic diagram showing another example of the apparatus for producing printed matter of the present invention.
2 differs from the printed product manufacturing apparatus 100 in that it applies a foam layer forming liquid to the substrate 19 by a curtain coater 30, and has a transparent layer forming liquid (clear ink) head 31 that applies the transparent layer forming liquid (clear ink) by an inkjet method. Therefore, in the printed product manufacturing apparatus 101, the curtain coater 30 and the active energy ray irradiation device 27 are an example of a foam layer forming means.
Furthermore, in the printed matter production apparatus 101, in addition to the operations performed by the printed matter production apparatus 101, the substrate 19 onto which clear ink has been applied by the transparent layer forming liquid (clear ink) head 31 is irradiated with active energy rays under predetermined irradiation conditions using the active energy ray irradiation device 17 to harden the clear ink and form a transparent layer. That is, in this example, the coated transparent layer forming liquid (clear ink) head 31 and the active energy ray irradiation device 17 are an example of a transparent layer forming means.

In this way, the printed matter manufacturing device 101 can form a transparent layer on the printed matter, which can further improve the durability of the formed uneven shape and image, and can produce printed matter that can maintain the design and image quality of the excellent uneven shape for a long period of time.

Next, an example of a flow of producing a printed matter in the method for producing a printed matter of the present invention will be described with reference to FIGS. 3A to 3G.
3A, a foam layer forming liquid containing a foaming agent 41 and a liquid composition 42 is applied onto a substrate 19. As a result, a layer 40 is formed from the foam layer forming liquid.
3B, a foam inhibitor 50 containing a polyfunctional monomer is applied onto and brought into contact with the layer 40 formed by the foam layer forming liquid. In this manner, the foam inhibitor 50 permeates the layer 40 formed by the foam layer forming liquid, and a foam inhibitor applied region 51 is formed in the layer 40 formed by the foam layer forming liquid.

Next, as shown in FIG. 3C, the layer 40 made of the foam layer forming liquid is irradiated with active energy rays (e.g., ultraviolet rays) using the active energy ray irradiation device 27 to harden the layer 40 made of the foam layer forming liquid, thereby forming a foam layer 43. When the layer 40 made of the foam layer forming liquid is hardened by the active energy ray irradiation device 27, the foam inhibitor application region 51 is also hardened to become the foam inhibition region 52. In the foam inhibition region 52, the polyfunctional monomer in the foam inhibitor 50 is three-dimensionally crosslinked, so that the layer is more firmly hardened.

Next, as shown in FIG. 3D, an ink receiving layer forming liquid containing a polymerizable compound a is applied onto the foam layer 43 to form a layer 60 of the ink receiving layer forming liquid.
Subsequently, as shown in FIG. 3E, an ink 70 containing a coloring material and a polymerizable compound b is applied onto the layer 60 made of the ink receiving layer forming liquid, thereby forming an ink application region 71.
Then, as shown in FIG. 3F, an active energy ray irradiation device 17 is used to irradiate the layer 60 made of the ink receiving layer forming liquid and the ink application area 71 with active energy rays (e.g., ultraviolet rays) to harden the layer 60 made of the ink receiving layer forming liquid and the ink application area 71, thereby forming an ink receiving layer 61 and an image 72.

3G, the foam layer 43 is heated using a heating device to foam the foaming agent 41, forming the foam layer 43 containing the foamed (volume expanded) foaming agent 44, thereby producing a printed matter. The foamed foaming agent 44 may disappear depending on, for example, the type of foaming agent, in which case the reference numeral 44 may become an air bubble (void).
Furthermore, as shown in FIG. 3G, the area that was previously the foaming-inhibited area 52 has been hardened more firmly, so that foaming of the foaming agent 41 is inhibited, and the degree of foaming can be appropriately controlled depending on the amount of foaming inhibitor 50 applied, etc.

In this way, a printed matter produced according to the example flow of the printed matter production method of the present invention shown in Figures 3A to 3G has excellent design and image quality due to the uneven shape, and can maintain the excellent design and image quality due to the uneven shape for a long period of time.

The following describes examples of the present invention, but the present invention is not limited to these examples.

<Preparation of Foam Layer Forming Liquid A1>
A foam layer forming liquid A1 was prepared by stirring 3 parts by mass of azodicarboxylic acid amide (manufactured by Eiwa Chemical Industry Co., Ltd.) as a foaming agent, 2 parts by mass of zinc naphthenate (manufactured by Tokyo Chemical Industry Co., Ltd.) as a foaming accelerator, 80 parts by mass of methoxypolyethylene glycol #400 acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) as a polymerizable solvent (polymerizable compound), 10 parts by mass of trimethylolpropane triacrylate (manufactured by Tomoe Engineering Co., Ltd.), and 5 parts by mass of Omnirad TPO (manufactured by IGM Resins) as a polymerization initiator.
The static surface tension of the foam layer forming liquid A1 at 25° C. was measured by a plate method using a platinum plate using a surface tensiometer DCAT (manufactured by Eiko Seiki Co., Ltd.) and was 35 mN/m. The viscosity of the foam layer forming liquid A1 at 25° C. was measured by a rheometer MCR302 (manufactured by Anton-Paar) using a CP50-1 (50 mm, 1° cone plate) at 25° C. and was 35 mPa·s.

<Preparation of Ink Receiving Layer Forming Liquid A2>
Ink receiving layer forming liquid A2 was prepared by stirring 94 parts by mass of 2-acryloyloxyethyl succinate (manufactured by Shin-Nakamura Chemical Co., Ltd.) as a polymerizable compound a, 5 parts by mass of Omnirad TPO (manufactured by IGM Resins) as a polymerization initiator, and 1 part by mass of BYK-UV-3510 (manufactured by BYK) as a surfactant.
The static surface tension and viscosity of the ink-receiving layer forming liquid A2 were measured in the same manner as for the foam layer forming liquid A1. The static surface tension of the ink-receiving layer forming liquid A2 at 25°C was 20 mN/m and the viscosity of the ink-receiving layer forming liquid A2 at 25°C was 190 mPa·s.

<Preparation of Black Ink A-Bk>
Black inks A-Bk were prepared by stirring 25 parts by mass of phenoxyethyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) as a polymerizable compound b, 26 parts by mass of acryloyl morpholine (manufactured by Tokyo Chemical Industry Co., Ltd.), 35 parts by mass of trimethylolpropane ethoxy triacrylate (manufactured by Daicel-Allnex Corporation), 5 parts by mass of Omnirad TPO (manufactured by IGM Resins) as a polymerization initiator, 2 parts by mass of Solsperse 32000 (manufactured by Lubrizol) as a surfactant/dispersant, and 7 parts by mass of SPECIAL BLACK 350 (black pigment, manufactured by BASF Japan) as a colorant.
When the static surface tension and viscosity were measured in the same manner as for the foam layer forming liquid A1, the static surface tension of the black ink A-Bk at 25°C was 24 mN/m and the viscosity at 25°C was 25 mPa·s.

<Preparation of Magenta Inks A to M>
Magenta inks A-M were prepared by stirring 25 parts by mass of phenoxyethyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) as the polymerizable compound b, 26 parts by mass of acryloyl morpholine (manufactured by Tokyo Chemical Industry Co., Ltd.), 35 parts by mass of trimethylolpropane ethoxy triacrylate (manufactured by Daicel-Allnex Corporation), 5 parts by mass of Omnirad TPO (manufactured by IGM Resins) as a polymerization initiator, 2 parts by mass of Solsperse 32000 (manufactured by Lubrizol) as a surfactant/dispersant, and 7 parts by mass of CINQUASIA MAGENTA RT-355-D (magenta pigment, manufactured by BASF Japan) as a colorant.
The static surface tension and viscosity were measured in the same manner as for foam layer forming liquid A1. The static surface tension of magenta inks A to M at 25°C was 24 mN/m, and the viscosity at 25°C was 25 mPa·s.

<Preparation of Cyan Inks A to C>
Cyan inks A-C were prepared by stirring 25 parts by mass of phenoxyethyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) as a polymerizable compound b, 26 parts by mass of acryloyl morpholine (manufactured by Tokyo Chemical Industry Co., Ltd.), 35 parts by mass of trimethylolpropane ethoxy triacrylate (manufactured by Daicel-Allnex Corporation), 5 parts by mass of Omnirad TPO (manufactured by IGM Resins) as a polymerization initiator, 2 parts by mass of Solsperse 32000 (manufactured by Lubrizol) as a surfactant/dispersant, and 40 parts by mass of IRGALITE BLUE GLVO (cyan pigment, manufactured by BASF Japan) as a colorant.
When the static surface tension and viscosity were measured in the same manner as for the foam layer forming liquid A1, the static surface tension of the cyan inks AC at 25° C. was 24 mN/m and the viscosity at 25° C. was 25 mPa·s.

<Preparation of Yellow Inks A to Y>
Yellow inks A-Y were prepared by stirring 25 parts by mass of phenoxyethyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) as the polymerizable compound b, 26 parts by mass of acryloyl morpholine (manufactured by Tokyo Chemical Industry Co., Ltd.), 35 parts by mass of trimethylolpropane ethoxy triacrylate (manufactured by Daicel-Allnex Corporation), 5 parts by mass of Omnirad TPO (manufactured by IGM Resins) as a polymerization initiator, 2 parts by mass of Solsperse 32000 (manufactured by Lubrizol) as a surfactant/dispersant, and 40 parts by mass of NOVOPERM YELLOW H2G (yellow pigment, manufactured by Clariant) as a colorant.
When the static surface tension and viscosity were measured in the same manner as for the foam layer forming liquid A1, the static surface tension of the yellow inks AY at 25° C. was 24 mN/m and the viscosity at 25° C. was 25 mPa·s.

Next, using the printed matter manufacturing apparatus 101 shown in FIG. 2 and the prepared foam layer forming liquid A1, ink receiving layer forming liquid A2, black inks A-Bk, magenta inks A-M, cyan inks A-C, and yellow inks A-Y, printed matter 1 was obtained as follows.
The foam layer forming liquid A1 was applied to an average thickness of 100 μm on a 9 mm thick MDF (medium density fiberboard, manufactured by Sumitomo Forestry Co., Ltd., N.P. Wood) substrate 19 using a curtain coater 30 (manufactured by Chefura, a laboratory flow coater). Thereafter, UV irradiation was performed using an active energy ray irradiation device 27 (manufactured by Hamamatsu Photonics K.K., linear irradiation type UV-LED light source GJ-75) from a position 10 mm away from the substrate surface to cure the foam layer forming liquid and form a foam layer.

Next, the ink receiving layer forming liquid A2 was applied onto the foam layer using a roller coater 28 (Easyproof, manufactured by Matsuo Sangyo Co., Ltd.) to an average thickness of 6 μm.
Next, the substrate was scanned at a speed of 15 m/min, and the black ink head 12, cyan ink head 13, magenta ink head 14, and yellow ink head 15 were heated to 40° C. using a GEN5 head (MH5420, 150 npi×4 rows) manufactured by Ricoh Industry Co., Ltd. as the ink ejection head 16, and the black ink A-Bk, magenta ink A-M, cyan ink A-C, and yellow ink A-Y were ejected at a droplet volume of 7 pL and a droplet speed of 7 m/s, respectively, so that a solid image with a dot density of 25% of 600 dpi×600 dpi for each color could be formed. In the following, the black ink A-Bk, magenta ink A-M, cyan ink A-C, and yellow ink A-Y may be collectively referred to as “color ink”.

Next, using an active energy ray irradiation device 17 (manufactured by Hamamatsu Photonics, linear irradiation type UV-LED light source GJ-75), UV was irradiated from a position 10 mm away from the substrate surface to cure the ink receiving layer forming liquid and ink, forming an ink receiving layer and an image. Here, the time from ejection of the yellow ink to curing was set to 6 seconds.

Then, the mixture was heated and foamed using heating device 18. The heating device used was a combination of a Hitachi Industrial Equipment Systems Co., Ltd. Lutex Blower G Series, a Kansai Electric Heater XS-2 for generating high-temperature hot air, and a Kansai Electric Heater High Blow Nozzle 50AL, adjusted to a wind speed of 30 m/sec from the nozzle tip and a temperature of 200°C at the nozzle tip. As a result, printed matter 1 was obtained.

Example 2
In Example 1, the same procedures as in Example 1 were carried out up to the point where the ink receiving layer forming liquid A2 was applied to an average thickness of 6 μm, and then the foamed layer was foamed by heating with the heating device 18, and then the color ink was ejected from the ejection head 16, and finally the ink receiving layer forming liquid and the ink were cured with the active energy ray irradiation device 17. Except for this, a printed matter 2 was obtained in the same manner as in Example 1.
In the second embodiment, the order of each process in the printed matter manufacturing apparatus 101 used in the first embodiment is changed by adjusting the order of conveying the substrate 19 and the timing of each process.

Example 3
In Example 1, the process was carried out in the same manner as in Example 1 until the foam layer forming liquid A1 was cured to form a foam layer, and then the foam layer was foamed by heating with a heating device 18, and then the ink receiving layer forming liquid A2 was applied to an average thickness of 6 μm, and then the color ink was ejected from the ejection head 16, and finally the ink receiving layer forming liquid and the ink were cured with an active energy ray irradiation device 17. Except for this, a printed matter 3 was obtained in the same manner as in Example 1. Note that in Example 3, the order of each step was changed in the same manner as in Example 2.

Example 4
Example 4 was obtained in the same manner as in Example 1, except that the foam layer forming liquid A1 in Example 1 was changed to the foam layer forming liquid B1 described below.

<Preparation of Foam Layer Forming Liquid B1>
A foam layer forming liquid B1 was prepared by stirring 15 parts by mass of Kureha Microsphere (H750, manufactured by Kureha Corporation) as a foaming agent, 40 parts by mass of isobornyl acrylate (manufactured by Tomoe Engineering Co., Ltd.) as a polymerizable solvent (polymerizable compound), 40 parts by mass of 2-acryloyloxyethyl phthalate (manufactured by Shin-Nakamura Chemical Co., Ltd.) as a polymerization initiator, and 5 parts by mass of Omnirad TPO (manufactured by IGM Resins).
The static surface tension and viscosity of foam layer forming liquid B1 were measured in the same manner as for foam layer forming liquid A1. The static surface tension of foam layer forming liquid B1 at 25°C was 33 mN/m and the viscosity at 25°C was 130 mPa·s.

Example 5
In Example 4, before the color inks were ejected by the ejection head 16, a transparent layer forming liquid (clear ink) A-CL prepared as described below was ejected from the transparent layer forming liquid (clear ink) head 31 at a droplet volume of 7 pL and a droplet speed of 7 m/s to form a solid image with a dot density of 100% of 600 dpi x 600 dpi, and then the color inks were ejected by the ejection head 16, and finally the ink receiving layer forming liquid A2, the color ink, and the clear ink A-CL were cured by the active energy ray irradiation device 17 to form an ink receiving layer, a transparent layer, and an image. Except for this, a printed matter 5 was obtained in the same manner as in Example 4. That is, in Example 5, the printed matter 5 was produced so that the substrate, the foam layer, the ink receiving layer, the transparent layer, and the image were formed in this order.

<<Preparation of Clear Ink A-CL>>
Clear ink A-CL was prepared by stirring 25 parts by mass of phenoxyethyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) as the polymerizable compound c, 26 parts by mass of acryloyl morpholine (manufactured by Tokyo Chemical Industry Co., Ltd.), 42 parts by mass of trimethylolpropane ethoxy triacrylate (manufactured by Daicel-Allnex Corporation), 5 parts by mass of Omnirad TPO (manufactured by IGM Resins) as a polymerization initiator, and 2 parts by weight of Solsperse 32000 (manufactured by Lubrizol) as a surfactant/dispersant.
When the static surface tension and viscosity were measured in the same manner as for foam layer forming liquid A1, the static surface tension of clear ink A-CL at 25°C was 24 mN/m and the viscosity at 25°C was 20 mPa·s.

(Example 6)
In Example 5, the color inks were ejected from the ejection head 16, and then the clear ink A-CL was ejected, and finally the ink-receiving layer forming liquid A2, the color inks, and the clear ink A-CL were cured by the active energy ray irradiation device 17 to form an ink-receiving layer, an image, and a transparent layer, and other than that, the printed matter 6 was obtained in the same manner as in Example 5. That is, in Example 6, the printed matter 6 was produced such that the substrate, the foam layer, the ink-receiving layer, the image, and the transparent layer were formed in this order.

(Example 7)
In Example 4, the foam layer forming liquid B1 was applied onto the substrate 19 to an average thickness of 100 μm, and then the foam inhibitor I prepared as described below was discharged from the head 11 in a droplet volume of 30 pL at a droplet speed of 7 m/s to impart a striped (striped) inhibition pattern to the foam layer with a dot density of 75 dpi in the head width direction and 600 dpi in the transport direction. In other words, in Example 7, the printed matter 7 having a striped uneven shape and a solid image formed on the surface was produced.

<<Preparation of Foam Inhibitor I>>
Foam inhibitor I was prepared by stirring 95 parts by mass of 1,6-hexanediol diacrylate (manufactured by Tomoe Engineering Co., Ltd.) as a polyfunctional monomer and 5 parts by mass of Omnirad TPO (manufactured by IGM Resins) as a polymerization initiator.
The static surface tension and viscosity of foam inhibitor I were measured in the same manner as for foam layer forming liquid A1. The static surface tension at 25° C. was 24 mN/m and the viscosity at 25° C. was 20 mPa·s.

(Example 8)
In Example 7, the active energy ray irradiation devices 17 and 27 were EC300/30/30mA manufactured by Iwasaki Electric Co., Ltd., and the inert gas blanket was connected to a compressor-equipped N ₂ gas generator (Maxi-Flow30, manufactured by Inhouse Gas Co., Ltd.) as an inert gas source at a pressure of 0.2 MPa·s, and N ₂ was flowed at a flow rate of 2 L/min to 10 L/min. The oxygen concentration was set to 500 ppm or less. The active energy rays were irradiated under irradiation conditions of an acceleration voltage of 30 kV and a dose of 30 kGy to cure the foam layer forming liquid B1 and cure the ink receiving layer and image. Except for this, a printed matter 8 was produced in the same manner as in Example 7.

(Example 9)
A printed matter 9 was produced in the same manner as in Example 1, except that, before applying the foam layer forming liquid A1 to the substrate 19, the substrate 19 was subjected to a corona discharge treatment at 2 m/min and 100 W using a TEC-4AX (manufactured by Kasuga Electric Co., Ltd.) with an electrode-substrate surface gap of 1 mm, so as to modify the surface of the substrate 19.

Example 10
A printed matter 10 was produced in the same manner as in Example 1, except that, before applying the ink receiving layer forming liquid A2 to the foam layer, the foam layer was subjected to a corona discharge treatment at 2 m/min and 100 W using a TEC-4AX (manufactured by Kasuga Electric Co., Ltd.) with an electrode-substrate surface gap of 1 mm, to modify the surface of the foam layer.

(Example 11)
In Example 1, before applying the foam layer forming liquid A1, the intermediate layer forming liquid 1 prepared as described below was applied to a thickness of 5 μm using a roller coater to the MDF substrate 19. Then, the printed matter 11 was obtained in the same manner as in Example 1, except that the applied liquid was cured using an active energy ray irradiation device (manufactured by Hamamatsu Photonics K.K., linear irradiation type UV-LED light source GJ-75).

<Preparation of adhesive layer forming liquid 1>
Adhesive layer forming liquid 1 was prepared by stirring 10 parts by mass of 1,4-cyclohexanedimethanol monoacrylate (manufactured by Mitsubishi Chemical Corporation) as a polymerizable compound e, 85 parts by mass of 2-acryloyloxyethyl phthalate (manufactured by Shin-Nakamura Chemical Co., Ltd.), and 5 parts by mass of Omnirad TPO (manufactured by IGM Resins) as a polymerization initiator.
The adhesive layer forming liquid 1 had a static surface tension of 40 mN/m at 25°C and a viscosity of 7,000 mPa·s at 25°C.
The static surface tension at 25° C. was measured by the plate method using an automatic surface tensiometer DY-300 manufactured by Kyowa Interface Science Co., Ltd. The viscosity at 25° C. was measured using a rheometer MCR301 manufactured by Anton Paar Co., Ltd., using a cone plate CP25-1, with the shear rate set to 10/s and the temperature set to 25° C. Hereinafter, the static surface tension and viscosity were measured in the same manner.

Example 12
A printed matter 12 was obtained in the same manner as in Example 11, except that the adhesive layer forming liquid 1 in Example 11 was changed to the adhesive layer forming liquid 2 prepared as follows.

<Preparation of adhesive layer forming liquid 2>
Adhesive layer forming liquid 2 was prepared by stirring 10 parts by mass of 2-acrylamide-2-methylpropanesulfonic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) as a polymerizable compound e, 85 parts by mass of 2-acryloyloxyethyl phthalate (manufactured by Shin-Nakamura Chemical Co., Ltd.), and 5 parts by mass of Omnirad TPO (manufactured by IGM Resins) as a polymerization initiator.
The adhesive layer forming liquid 2 had a static surface tension of 40 mN/m at 25°C and a viscosity of 6,000 mPa·s at 25°C.

(Example 13)
In Example 11, the adhesive layer forming liquid 1 was changed to adhesive layer forming liquid 3, which was a dispersion-type resin, Boncoat W-26 (manufactured by DIC Corporation), and after applying the adhesive layer forming liquid 3, the printed matter 13 was obtained in the same manner as in Example 11, except that it was dried in an oven at 100°C for 1 minute.

(Example 14)
In Example 11, the adhesive layer forming liquid 1 was changed to an adhesive layer forming liquid 4, which was Finetac CT-5020 (manufactured by DIC Corporation) as a soluble resin, and after applying the adhesive layer forming liquid 4, the printed matter 14 was obtained in the same manner as in Example 11, except that it was dried in an oven at 100°C for 1 minute.

(Example 15)
A printed matter 15 was obtained in the same manner as in Example 11, except that the adhesive layer forming liquid 1 in Example 11 was changed to the adhesive layer forming liquid 5 prepared as follows.

<Preparation of intermediate layer forming solution 5>
Intermediate layer forming solution 5 was prepared by stirring 90 parts by mass of Boncoat W-26 (manufactured by DIC Corporation) as a dispersion type resin and 10 parts by mass of organosilica sol IPA-ST-UP (manufactured by Nissan Chemical Industries, Ltd.) as solid fine particles.

(Example 16)
A printed matter 16 was obtained in the same manner as in Example 11, except that the adhesive layer forming liquid 1 in Example 11 was changed to the adhesive layer forming liquid 6 prepared as follows.

<Preparation of intermediate layer forming solution 6>
Adhesive layer forming liquid 6 was prepared by stirring 90 parts by mass of Finetack CT-5020 (manufactured by DIC Corporation) as a soluble resin and 10 parts by mass of organosilica sol MEK-ST-UP (manufactured by Nissan Chemical Industries, Ltd.) as solid fine particles.

(Example 17)
<Preparation of Filler-Containing Layer Forming Liquid 1>
In Example 1, after forming the ink receiving layer and the image, a roller coater was used to apply filler-containing layer forming liquid 1 prepared as described below onto the image to an average thickness of 20 μm, and the base material 19 was irradiated with ultraviolet rays from an irradiation distance of 10 mm using an active energy ray irradiation device 21 to cure the filler-containing layer forming liquid 1. Finally, the foam layer was foamed using a heating device 22, thereby obtaining a printed matter 17 having a filler-containing layer.

<Preparation of Filler-Containing Layer Forming Liquid 1>
A filler-containing layer forming liquid 1 was prepared by mixing and stirring 84.9 parts by mass of 2-acryloyloxyethyl succinate (manufactured by Shin-Nakamura Chemical Co., Ltd.) as a polymerizable compound d, 5 parts by mass of Omnirad TPO (manufactured by IGM Resins) as an initiator, 0.1 parts by mass of BYK-UV-3510 (manufactured by BYK) as a surfactant, and 10 parts by mass of silica (average primary particle size: 0.6 μm, refractive index: 1.46) as a filler.
The filler-containing layer forming liquid had a static surface tension of 29 mN/m at 25°C and a viscosity of 400 mPa·s at 25°C.

(Comparative Example 1)
A printed matter 18 was produced in the same manner as in Example 4, except that the application and curing of the ink-receiving layer forming liquid A2 were not carried out and an ink-receiving layer was not formed.

(Comparative Example 2)
A printed matter 19 was produced in the same manner as in Example 4, except that the application and curing of the foam layer forming liquid B1 were not carried out and a foam layer was not formed.

<Evaluation>
Next, the image quality (image quality, durability) and design were evaluated as follows for the obtained printed matter 1 to 19 of Examples 1 to 17 and Comparative Examples 1 and 2. The evaluation results are shown in Table 1.

<<Evaluation of image quality>>
The color development of the solid image formed with the color inks was visually confirmed and evaluated according to the following criteria: If the evaluation was "good" or better, it was at a level that was acceptable for practical use.
[Evaluation Criteria for Color Development]
⊚: No pattern due to uneven color density can be confirmed within the solid image surface. ◯: Pattern due to uneven color density can be confirmed within the solid image surface, but is not noticeable. ×: Conspicuous pattern due to uneven color density can be confirmed within the solid image surface.

Next, the surface of the printed matter on which the image was formed was rubbed 100 times with a nonwoven fabric, and then scratched three times with a fingernail to evaluate the durability of the solid image formed with the color ink according to the following criteria. Note that an evaluation of "◯" or higher indicates a satisfactory level for practical use.
[Durability evaluation criteria]
◎: No scratches on the image due to rubbing can be seen, and no peeling of the image from the base material can be seen. ◯: Scratches on the image due to rubbing can be seen, but no peeling of the image from the base material can be seen. ×: Scratches on the image due to rubbing can be seen, and peeling of the image from the base material can be seen.

<<Evaluation of Design>>
The design of the produced prints was judged according to the following criteria. The evaluation criteria for Examples 1 to 6 and 9 to 17, which do not have a striped uneven shape, and the evaluation criteria for Examples 7 to 8 and Comparative Examples 1 and 2, which have a striped uneven shape, were different from each other as shown below. The evaluation of "◯" or higher is at a level that is acceptable for practical use.

[Evaluation criteria for design in Examples 1 to 6 and 9 to 17]
⊚: The difference in level between the printed part (a part on which at least the foam layer, the ink receiving layer, and the image are formed on the substrate) and the non-printed part (only the substrate) in the printed matter is 400 μm or more. ◯: The difference in level between the printed part and the non-printed part in the printed matter is 150 μm or more and less than 400 μm. ×: The difference in level between the printed part and the non-printed part in the printed matter is less than 150 μm.

In addition, when evaluating the design of Examples 1 to 6 and 9 to 17, the height of the step between the printed and non-printed areas was measured by shape measurement using a laser microscope VK-X100 (manufactured by Keyence Corporation).

[Evaluation criteria for design in Examples 7 to 8 and Comparative Examples 1 to 2]
⊚: The steps in the striped uneven shape can be confirmed by visual inspection only. ◯: The steps in the striped uneven shape cannot be confirmed by visual inspection, but can be confirmed by touch. ×: The steps in the striped uneven shape cannot be confirmed by touch.

From the results shown in Table 1, it can be seen that printed matter 1 to 17 of Examples 1 to 17 are superior in image quality (image quality, durability) and design compared to printed matter 18 and 19 of Comparative Examples 1 and 2.
In particular, the printed matter 17 having the filler-containing layer was a printed matter having even more excellent abrasion resistance.

As described above, the method for producing a printed matter of the present invention includes a foam layer forming step of forming a foam layer containing a foaming agent, an ink receiving layer forming step of forming an ink receiving layer containing a polymer of polymerizable compound a on the foam layer, an image forming step of applying an ink containing a colorant and polymerizable compound b onto the ink receiving layer to form an image, and a foaming step of heating the foam layer to foam it.
As a result, the method for producing a printed matter of the present invention can produce a printed matter that has excellent design and image quality due to the uneven shape, and that can retain the excellent design and image quality due to the uneven shape for a long period of time.

For example, aspects of the present invention are as follows.
<1> A foam layer forming step of forming a foam layer containing a foaming agent;
an ink receiving layer forming step of forming an ink receiving layer containing a polymer of the polymerizable compound a on the foam layer;
an image forming step of applying an ink containing a coloring material and a polymerizable compound b onto the ink receiving layer to form an image;
a foaming step of heating the foam layer to foam it;
A method for producing a printed matter comprising the steps of:
<2> In the foam layer forming step,
The method for producing a printed matter according to <1> above, further comprising applying a foam layer forming liquid containing the foaming agent onto a substrate, and then curing the foam layer forming liquid to form the foam layer.
<3> In the ink receiving layer forming step,
The method for producing a printed matter according to any one of <1> and <2>, further comprising applying an ink-receiving layer forming liquid containing the polymerizable compound a onto the foam layer, and then curing the ink-receiving layer forming liquid to form the ink-receiving layer.
<4> In the image forming process,
The method for producing a printed matter according to <3> above, further comprising applying the ink onto the ink receiving layer and then curing the ink to form the image.
<5> The method for producing a printed matter according to <4>, wherein the ink receiving layer forming liquid in the ink receiving layer forming step and the ink in the image forming step are cured simultaneously.
<6> In the image forming process,
The method for producing a printed matter according to any one of <1> to <5>, wherein the ink is applied onto the ink receiving layer by an inkjet method.
<7> The method for producing a printed matter according to any one of <1> to <6>, wherein the foaming step is performed after the image forming step.
<8> The method for producing a printed matter according to any one of <1> to <7>, wherein the foaming agent is a thermally expandable microcapsule.
<9> The method for producing a printed matter according to any one of <1> to <8>, further comprising a transparent layer forming step of forming a transparent layer containing a polymer of a polymerizable compound c on at least one of the ink receiving layer and the image.
<10> In the transparent layer forming step,
The method for producing a printed matter according to <9>, further comprising forming the transparent layer at least on the image.
<11> The method for producing a printed matter according to any one of <1> to <10>, further comprising a foam inhibitor application step of applying and contacting a foam inhibitor containing a polyfunctional monomer to a predetermined region of the foam layer.
<12> The method for producing a printed matter according to <11>, wherein in the foaming inhibitor applying step, the foaming inhibitor is applied by an inkjet system.
<13> The method for producing a printed matter according to any one of <1> to <12>, further comprising, prior to the foam layer forming step, a substrate surface modification step of performing a corona discharge treatment on the substrate on which the foam layer is to be formed, thereby modifying the substrate surface.
<14> The method for producing a printed matter according to any one of <1> to <13>, further comprising, after the foam layer forming step, a foam layer surface modification step of performing a corona discharge treatment on the foam layer to modify the surface of the foam layer.
<15> The method for producing a printed matter according to any one of <1> to <14>, further comprising forming a filler-containing layer on at least one of the ink receiving layer and the image.
<16> In the filler-containing layer forming step,
The method for producing a printed matter according to <15>, further comprising applying a filler-containing layer forming liquid containing the filler and a polymerizable compound d onto at least one of the ink receiving layer and the image, and then curing the filler-containing layer forming liquid to form the filler-containing layer.
<17> Before the foam layer forming step,
The method for producing a printed matter according to any one of <1> to <16>, further comprising an adhesive layer forming step of forming an adhesive layer on a substrate to bond the substrate and the foam layer.
<18> In the adhesive layer forming step,
applying an adhesive layer forming liquid for forming the adhesive layer onto the base material, and then curing the adhesive layer forming liquid to form the adhesive layer;
The method for producing a printed matter according to <17>, wherein the adhesive layer forming liquid contains at least one of a polymerizable compound e, a dispersion type resin, and a solution type resin.
<19> A foam layer forming means for forming a foam layer containing a foaming agent;
an ink-receiving layer forming means for forming an ink-receiving layer containing a polymer of the polymerizable compound a on the foam layer;
an image forming means for applying an ink containing a coloring material and a polymerizable compound b onto the ink receiving layer to form an image;
A foaming means for heating and foaming the foam layer;
The present invention relates to a printing production apparatus comprising:
<20> A bubble-containing layer containing bubbles;
an ink-receiving layer located on the bubble-containing layer and containing polymer A;
an image formed on the ink receiving layer using a cured product of an ink containing a colorant and a polymer B;
The printed matter is characterized by having:

The method for producing a printed matter described in any one of <1> to <18>, the device for producing a printed matter described in <19>, and the printed matter described in <20> can solve the problems of the prior art and achieve the object of the present invention.

LIST OF SYMBOLS 10 Application roller 11 Head for foaming inhibitor 12 Head for black 13 Head for cyan 14 Head for magenta 15 Head for yellow 16 Discharge head 17 Active energy ray irradiation device 18 Heating device 19 Substrate 20 Conveyor belt 21 Feed-out roller 22 Take-up roller 27 Active energy ray irradiation device 28 Active energy ray irradiation device 30 Curtain coater 31 Head for transparent layer forming liquid (clear ink) 40 Layer made of foaming layer forming liquid 41 Foaming agent 42 Liquid composition 43 Foamed layer 44 Foamed foaming agent or bubbles 50 Foaming inhibitor 51 Foaming inhibitor applied region 52 Foaming suppressed region 60 Layer made of ink receiving layer forming liquid 61 Ink receiving layer 70 Ink 71 Ink applied region 72 Image 100 Apparatus for producing printed matter 101 Apparatus for producing printed matter

Patent No. 5195999

Claims (15)

a foam layer forming step of forming a foam layer containing a foaming agent;
an ink-receiving layer forming step of applying an ink-receiving layer forming liquid containing a polymerizable compound a onto the foam layer to form an ink-receiving layer;
an image forming step of applying an ink containing a coloring material and a polymerizable compound b onto the ink receiving layer to form an image;
a foaming step of heating the foam layer to foam it;
Including,
A method for producing a printed matter, comprising the steps of curing the ink receiving layer forming liquid and curing the ink in a single step . In the foam layer forming step,
The method for producing a printed matter according to claim 1 , further comprising the steps of: applying a foam layer forming liquid containing the foaming agent onto a substrate; and curing the foam layer forming liquid to form the foam layer. In the image forming process,
The method for producing a printed matter according to claim 1 , wherein the ink is applied onto the ink receiving layer by an inkjet method. The method for producing a printed matter according to claim 1 , wherein the foaming step is carried out after the image forming step. The method for producing a printed matter according to claim 1 , wherein the foaming agent is a thermally expandable microcapsule. The method for producing a printed matter according to claim 1 , further comprising a transparent layer forming step of forming a transparent layer containing a polymer of a polymerizable compound c on at least one of the ink receiving layer and the image. In the transparent layer forming step,
The method for producing a printed matter according to claim 6 , further comprising forming the transparent layer on at least the image. The method for producing a printed matter according to claim 1 , further comprising a foaming inhibitor applying step of applying a foaming inhibitor containing a polyfunctional monomer to a predetermined region of the foam layer and contacting the predetermined region with the foaming inhibitor. The method for producing a printed matter according to claim 8 , wherein in the foaming inhibitor applying step, the foaming inhibitor is applied by an inkjet system. The method for producing a printed matter according to claim 1 , further comprising, prior to the foam layer forming step, a substrate surface modification step of performing a corona discharge treatment on the substrate on which the foam layer is to be formed to modify the surface thereof. The method for producing a printed matter according to claim 1 , further comprising, after the foam layer forming step, a foam layer surface modifying step of modifying the surface of the foam layer by subjecting the foam layer to a corona discharge treatment. The method for producing a printed matter according to claim 1 , further comprising a filler-containing layer forming step of forming a filler-containing layer containing a filler on at least one of the ink receiving layer and the image. In the filler-containing layer forming step,
The method for producing a printed matter according to claim 12, further comprising applying a filler-containing layer forming liquid containing the filler and a polymerizable compound d onto at least one of the ink receiving layer and the image, and then curing the filler-containing layer forming liquid to form the filler-containing layer. Before the foam layer forming step,
The method for producing a printed matter according to claim 1 , further comprising an adhesive layer forming step of forming an adhesive layer on a substrate to bond the substrate and the foam layer. In the adhesive layer forming step,
applying an adhesive layer forming liquid for forming the adhesive layer onto the base material, and then curing the adhesive layer forming liquid to form the adhesive layer;
The method for producing a printed matter according to claim 14 , wherein the adhesive layer forming liquid contains at least one of a polymerizable compound e, a dispersion type resin, and a solution type resin.

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