UV-shielding ink composition and method for producing substrate having embossed surface using the same

Abstract

To improve workability in a removal step for forming an embossed shape in a method for producing a substrate having an embossed surface using an ultraviolet light-shielding ink composition. [Solution] An ultraviolet ray blocking ink composition for inkjet printing, comprising: 65.0 mass % or more of a photopolymerizable monomer; 0.5 mass % or more and less than 3.0 mass % of an ultraviolet ray absorber; and 5.0 mass % or more and less than 20.0 mass % of a non-polymerizable material relative to the ink composition; the photopolymerizable monomer and the non-polymerizable material respectively contain a photopolymerizable monomer having a glass transition temperature of 60°C or more and a non-polymerizable material having a glass transition temperature of 60°C or more; and the total content of the photopolymerizable monomer having a glass transition temperature of 60°C or more and the non-polymerizable compound in the ultraviolet ray blocking ink composition is 20 mass % or more.

Description

[Technical Field]

[0001] The present invention relates to an ink composition for forming a print layer for blocking ultraviolet light (an ultraviolet light-blocking ink composition), and a method for producing a substrate having an embossed surface using the same. [Background technology]

[0002] Embossing methods for creating a textured pattern on the surface of an article are known. Examples include a method in which an ultraviolet-curable resin composition applied to the surface of a workpiece is irradiated with ultraviolet light through a transparent belt or the like printed with ultraviolet-blocking ink, thereby curing only a portion of the ultraviolet-curable resin composition and creating an embossed pattern (Patent Document 1); a method in which an ink containing an ultraviolet absorber is printed on a photocurable resin coating applied to a substrate, and the printed portion is embossed by irradiating it with light to create a recessed portion (Patent Document 2); a method in which an ultraviolet absorber is present in the patterned portion of the surface of an object, an ultraviolet-curable unsaturated polyester resin film is applied, and then ultraviolet light is irradiated to partially cure the resin film and create a textured portion (Patent Documents 3 and 4); and a method in which a patterned surface printed with ink containing an ultraviolet absorber is covered with an ultraviolet-sensitive curable resin film, and then ultraviolet light is irradiated to cure the resin film, thereby forming recesses corresponding to the printed pattern and creating an embossed pattern (Patent Document 5).

[0003] Furthermore, in recent years, digital embossing methods using inkjet printing technology have also been proposed. Digital embossing allows various embossed shapes to be created easily and at low cost. For example, by scanning a desired shape and reproducing it using inkjet printing, a wide variety of processed products can be produced in small quantities.

[0004] As a digital embossing method, for example, a method has been proposed in which droplets (3) made of an acrylate compound are sprayed onto a liquid layer (2) formed on the surface of an object (1) in accordance with a digital template, and then the liquid layer (2) and droplets (3) are UV-cured to shape the surface of the object (1) (Patent Document 6); a method in which a photopolymerizable resin film A is applied to the surface of an object, liquid B containing a photocrosslinkable monomer or oligomer is applied to part of the surface of resin film A, resin film A and liquid B are polymerized, and the polymer of liquid B and part of the cured resin film A are mechanically removed to obtain a cured resin film A having a three-dimensional structure (Patent Documents 7 and 8); etc.

[0005] As in the above-mentioned Cited Documents 7 and 8, digital embossing methods have been proposed that include a step of mechanically removing a portion of the photocured resin layer, but it has been difficult to obtain a desired embossed shape using these methods. That is, the ink composition printed to block ultraviolet light: 1) fails to block ultraviolet light sufficiently, causing the underlayer made of photopolymerizable resin to be completely photocured and making it impossible to remove the underlayer; 2) blocks ultraviolet light excessively, causing the underlayer made of photopolymerizable resin that should be photocured to be unable to be sufficiently cured, leaving it in a liquid state and removing more of the underlayer than necessary; or 3) the ink composition does not have printability for inkjet printing, making it difficult to perform appropriate inkjet printing.

[0006] To solve this problem, an ultraviolet ray blocking ink composition for inkjet printing and a digital embossing method using the same have been proposed (Patent Document 9); specifically, the proposed ultraviolet ray blocking ink composition contains 55.0% by mass or more of a photopolymerizable monomer, 3.0% by mass or more and less than 15.0% by mass of an ultraviolet ray absorber, and 10.0% by mass or more and less than 30.0% by mass of a non-polymerizable material, and the content of a polyfunctional monomer in the photopolymerizable monomer is 50.0% by mass or more relative to the photopolymerizable monomer.

[0007] In addition, a method is known in which a protective liquid for protecting an image, which contains an ultraviolet absorber and a resin having film-forming ability, is ink-jet printed onto the image to protect the image from light degradation (Patent Document 10). [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 53-51253 [Patent Document 2] Japanese Patent Application Publication No. 48-4602 [Patent Document 3] Japanese Patent Application Publication No. 48-64163 [Patent Document 4] Japanese Patent Application Publication No. 50-3139 [Patent Document 5] Japanese Unexamined Patent Publication No. 48-22143 [Patent Document 6] European Patent No. 3109056 [Patent Document 7] International Publication No. 2020 / 039361 [Patent Document 8] International Publication No. 2018 / 069874 [Patent Document 9] Japanese Patent Application Publication No. 2024-065276 [Patent Document 10] Japanese Patent Application Laid-Open No. 2000-225695 Summary of the Invention [Problem to be solved by the invention]

[0009] As mentioned above, Patent Document 9 proposes a digital embossing method using an ultraviolet light-blocking ink composition for inkjet printing. Specifically, the proposed method involves inkjet printing the ultraviolet light-blocking ink composition onto an uncured coating film containing a photopolymerizable compound coated on a substrate (Step A); irradiating the coating film with ultraviolet light (Step B); and removing the coating film in the areas printed with the ultraviolet light-blocking ink composition (Step C), thereby obtaining an embossed surface. However, removing the coating film in the areas printed with the ultraviolet light-blocking ink composition (Step C) can be difficult. For example, when attempting to remove the coating film with a brush or the like, the components to be removed can adhere to the brush, reducing workability.

[0010] Therefore, an object of the present invention is to improve the workability of the removal step for creating the embossed shape in a method for manufacturing a substrate having an embossed surface using an ultraviolet light-shielding ink composition (digital embossing method) by optimizing the composition of the ultraviolet light-shielding ink composition. [Means for solving the problem]

[0011] That is, a first aspect of the present invention relates to an ultraviolet light blocking ink composition shown below. [1] An ultraviolet ray shielding ink composition for inkjet printing, comprising, relative to the ink composition, 65.0% by mass or more of a photopolymerizable monomer, 5.0% by mass or more and less than 20.0% by mass of a non-polymerizable material, and 0.5% by mass or more and less than 3.0% by mass of an ultraviolet ray absorber; the photopolymerizable monomer and the non-polymerizable material respectively contain a photopolymerizable monomer having a glass transition temperature of 60°C or more and a non-polymerizable material having a glass transition temperature of 60°C or more; and the total content of the photopolymerizable monomer having a glass transition temperature of 60°C or more and the non-polymerizable compound is 20% by mass or more of the ultraviolet ray shielding ink composition.

[0012] Preferably, the present invention relates to an ultraviolet light blocking ink composition as described below. [2] The ultraviolet ray blocking ink composition according to [1] above, wherein the content of the polyfunctional monomer in the photopolymerizable monomer is 50.0 mass % or more relative to the photopolymerizable monomer. [3] The ultraviolet ray blocking ink composition according to [1] or [2] above, wherein the photopolymerizable monomer with a glass transition temperature of 60°C or higher includes a photopolymerizable monomer with a glass transition temperature of 80°C or higher. [4] The ultraviolet ray blocking ink composition according to any one of [1] to [3] above, which is used for ink jet printing on an uncured coating film containing a photopolymerizable compound.

[0013] The second aspect of the present invention relates to a method for producing a substrate having an embossed surface, which will be described below. [5] A method for producing a substrate having an embossed surface, comprising: step A: inkjet printing the ultraviolet ray blocking ink composition according to item [1] above onto an uncured coating film containing a photopolymerizable compound that is coated on a substrate; step B: irradiating the coating film printed with the ultraviolet ray blocking ink composition with ultraviolet rays; and step C: removing the coating film in the area printed with the ultraviolet ray blocking ink composition.

[0014] Preferably, the present invention relates to a method for producing a substrate having an embossed surface, as follows: [6] The method according to [5] above, wherein the coating film further contains a photopolymerization initiator. [7] The method according to [5] or [6] above, wherein the coating film has a thickness of 30 μm or more. [8] The method according to any one of [5] to [7] above, wherein the step C is a mechanical removal step. [Effects of the Invention]

[0015] The method for producing a substrate having an embossed surface of the present invention includes: step A: inkjet printing an ultraviolet ray blocking ink composition onto an uncured coating film containing a photopolymerizable compound; step B: irradiating the coating film printed with the ultraviolet ray blocking ink composition with ultraviolet rays; and step C: removing the coating film in the area printed with the ultraviolet ray blocking ink composition; and the removal of the coating film in step C is easy and has good workability. Therefore, a substrate having an embossed surface can be produced simply and at low cost, and the design properties of the embossing can also be improved. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is a diagram showing a manufacturing flow of a substrate having an embossed surface. DETAILED DESCRIPTION OF THE INVENTION

[0017] [1. UV-shielding ink composition] The ultraviolet ray blocking ink composition of the present invention contains 1) a photopolymerizable monomer, 2) a non-polymerizable material, 3) an ultraviolet ray absorber, and may further contain 4) other components.

[0018] The ultraviolet ray blocking ink composition of the present invention can be printed by an inkjet method and then irradiated with ultraviolet rays, causing the photopolymerizable monomer to polymerize and solidify, but the degree of solidification is such that it can be mechanically removed. Furthermore, because the ultraviolet ray blocking ink composition of the present invention contains an ultraviolet absorber, it is possible to prevent excessive ultraviolet rays from being irradiated onto the layer (underlying layer) that underlies the region where the printed layer of the ultraviolet ray blocking ink composition is formed. As a result, even if the underlying layer is made of a photocurable resin, it is not completely cured, and the underlying layer can be semi-cured to a degree that it can be mechanically removed.

[0019] [1-1. Photopolymerizable Monomer] The photopolymerizable monomer contained in the ultraviolet ray shielding ink composition is preferably a monomer having photoradical polymerizability or photocationic polymerizability, and more preferably a monomer having photoradical polymerizability. The ultraviolet ray shielding ink composition contains at least a polyfunctional photopolymerizable monomer, and may contain a combination of a polyfunctional photopolymerizable monomer and a monofunctional photopolymerizable monomer.

[0020] [1-1-1. Polyfunctional photopolymerizable monomer (polyfunctional monomer)] A polyfunctional photopolymerizable monomer is a compound having two or more ethylenically unsaturated bonds. Examples of polyfunctional photopolymerizable monomers include the following polyfunctional (meth)acrylate compounds and vinyl ether group-containing (meth)acrylate compounds.

[0021] The polyfunctional (meth)acrylate compound may be bifunctional or trifunctional or higher. Examples of bifunctional (meth)acrylate compounds include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, pentaerythritol, methyl methacrylate ... Ethyl glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, hydroxypivalyl hydroxypivalate di(meth)acrylate, hydroxypivalyl hydroxypivalate dicaprolactonate di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,2-hexanediol di(meth)acrylate, 1,5-hexanediol di(meth)acrylate, 2,5-hexanediol di(meth)acrylate, 1,7-heptanediol di(meth)acrylate Acrylate, 1,8-octanediol di(meth)acrylate, 1,2-octanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,2-decanediol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, 1,2-dodecanediol di(meth)acrylate, 1,14-tetradecanediol di(meth)acrylate, 1,2-tetradecanediol di(meth)acrylate, 1, 16-Hexadecanediol di(meth)acrylate, 1,2-Hexadecanediol di(meth)acrylate, 2-Methyl-2,4-pentanediol di(meth)acrylate, 3-Methyl-1,5-pentanediol di(meth)acrylate, 2-Methyl-2-propyl-1,3-propanediol di(meth)acrylate, 2,4-Dimethyl-2,4-pentanediol di(meth)acrylate, 2,2-Diethyl-1,3-propanediol di(meth)acrylate, 2,2,4-Trimethyl-1,3-Pentanediol di(meth)acrylate, dimethylol octane di(meth)acrylate, 2-ethyl-1,3-hexanediol di(meth)acrylate, 2,5-dimethyl-2,5-hexanediol di(meth)acrylate, 2-methyl-1,8-octanedi, Di(meth)acrylate, 2-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, 2,4-diethyl-1,5-pentanediol di(meth)acrylate, tricyclodecanedimethylol di(meth)acrylate, tricyclodecanedimethylol dicaprolactonate di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, bisphenol A tetraethyleneoxide adduct di(meth)acrylate, bisphenol F tetraethyleneoxide adduct di(meth)acrylate, bisphenol S tetraethyleneoxide adduct di(meth)acrylate acrylate, hydrogenated bisphenol A tetraethylene oxide adduct di(meth)acrylate, hydrogenated bisphenol F tetraethylene oxide adduct di(meth)acrylate, hydrogenated bisphenol A di(meth)acrylate, hydrogenated bisphenol F di(meth)acrylate, bisphenol A tetraethylene oxide adduct dicaprolactonate di(meth)acrylate, bisphenol F tetraethylene oxide adduct dicaprolactonate di(meth)acrylate, di(meth)acrylates of polyhydric alcohols such as glycerin, pentaerythritol, diglycerin, ditrimethylolpropane, and dipentaerythritol.

[0022] Examples of trifunctional (meth)acrylate compounds include glycerin tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolpropane tricaprolactonate tri(meth)acrylate, trimethylolethane tri(meth)acrylate, trimethylolhexane tri(meth)acrylate, trimethyloloctane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, and the like; and 3EO (ethylene oxide)-modified, 6EO-modified, and 9EO-modified products thereof (3EO-modified trimethylolpropane tri(meth)acrylate, 3EO-modified trimethylolethane tri(meth)acrylate, 3EO-modified trimethylolhexane tri(meth)acrylate, and the like).

[0023] Examples of tetrafunctional or higher (meth)acrylate compounds include trimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tetracaprolactonate tetra(meth)acrylate, diglycerin tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, ditrimethylolpropane tetracaprolactonate tetra(meth)acrylate, ditrimethylolethane tetra(meth)acrylate, ditrimethylolbutane tetra(meth)acrylate, Examples of the acrylates include tetra(meth)acrylate, ditrimethylolhexane tetra(meth)acrylate, ditrimethyloloctane tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tripentaerythritol hexa(meth)acrylate, tripentaerythritol hepta(meth)acrylate, tripentaerythritol octa(meth)acrylate, and tripentaerythritol polyalkylene oxide hepta(meth)acrylate.

[0024] Examples of vinyl ether group-containing (meth)acrylate compounds include 2-vinyloxyethyl (meth)acrylate, 3-vinyloxypropyl (meth)acrylate, 1-methyl-2-vinyloxyethyl (meth)acrylate, 2-vinyloxypropyl (meth)acrylate, 4-vinyloxybutyl (meth)acrylate, 1-methyl-3-vinyloxypropyl (meth)acrylate, 1-vinyloxymethylpropyl (meth)acrylate, and 2-methyl-3-vinyloxypropyl (meth)acrylate. , (meth)acrylate-3-methyl-3-vinyloxypropyl, (meth)acrylate-1,1-dimethyl-2-vinyloxyethyl, (meth)acrylate-3-vinyloxybutyl, (meth)acrylate-1-methyl-2-vinyloxypropyl, (meth)acrylate-2-vinyloxybutyl, (meth)acrylate-4-vinyloxycyclohexyl, (meth)acrylate-5-vinyloxypentyl, (meth)acrylate-6-vinyloxyhexyl, (meth)acrylate-4-vinyloxymethylcyclohexyl Cylmethyl, (meth)acrylate-3-vinyloxymethylcyclohexylmethyl, (meth)acrylate-2-vinyloxymethylcyclohexylmethyl, (meth)acrylate-p-vinyloxymethylphenylmethyl, (meth)acrylate-m-vinyloxymethylphenylmethyl, (meth)acrylate-o-vinyloxymethylphenylmethyl, (meth)acrylate-2-(vinyloxyisopropoxy)ethyl, (meth)acrylate-2-(vinyloxyethoxy)propyl, (meth)acrylate-2-( (vinyloxyethoxy)isopropyl (meth)acrylate, 2-(vinyloxyisopropoxy)propyl (meth)acrylate, 2-(vinyloxyisopropoxy)isopropyl (meth)acrylate, 2-(vinyloxyethoxyethoxy)ethyl (meth)acrylate, 2-(vinyloxyethoxyisopropoxy)ethyl (meth)acrylate, 2-(vinyloxyisopropoxyethoxy)ethyl (meth)acrylate, 2-(vinyloxyisopropoxyisopropoxy)ethyl (meth)acrylate, and the like.

[0025] The polyfunctional photopolymerizable monomer contained in the UV-shielding ink composition is preferably a monomer with reduced odor. This is because the UV-shielding ink composition is semi-cured upon light irradiation, and is not completely cured. Preferred examples of the polyfunctional photopolymerizable monomer include 1,6-hexanediol diacrylate (bifunctional), neopentyl glycol PO-modified diacrylate (bifunctional), and EO-modified trimethylolpropane triacrylate (trifunctional).

[0026] [1-1-2. Monofunctional photopolymerizable monomers (monofunctional monomers)] Examples of monofunctional photopolymerizable monomers include unsaturated carboxylic acid compounds, alkyl (meth)acrylate compounds, hydroxyl group-containing (meth)acrylate compounds, halogen-containing (meth)acrylate compounds, ether group-containing (meth)acrylate compounds, carboxyl group-containing (meth)acrylate compounds, other (meth)acrylate compounds, styrene compounds, N-vinyl compounds, arylate compounds, and other compounds having one ethylenically unsaturated bond.

[0027] Examples of the monofunctional unsaturated carboxylic acid compound include unsaturated carboxylic acids such as (meth)acrylic acid, itaconic acid, crotonic acid, isocrotonic acid, fumaric acid, and maleic acid, as well as salts and acid anhydrides thereof.

[0028] Examples of monofunctional alkyl (meth)acrylate compounds include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl acrylate, amyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, isooctyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, Examples of the acrylates include isodecyl (meth)acrylate, isomyristyl (meth)acrylate, octadecyl (meth)acrylate, dicyclopentanyl (meth)acrylate, tridecyl (meth)acrylate, nonyl (meth)acrylate, hexadecyl (meth)acrylate, myristyl (meth)acrylate, isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, norbornyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, 1-adamantyl (meth)acrylate, 3,5,5-trimethylcyclohexyl acrylate, and 4-t-butylcyclohexyl (meth)acrylate.

[0029] Examples of the monofunctional hydroxyl group-containing (meth)acrylate compound include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, hydroxypentyl (meth)acrylate, 2-hydroxy-3-methoxypropyl (meth)acrylate, 2-hydroxy-3-butoxypropyl (meth)acrylate, diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, polyethylene glycol mono(meth)acrylate, dipropylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, Examples of the alkylene glycol-modified (meth)acrylates include (poly)alkylene glycol-modified (meth)acrylates such as ethylene glycol mono(meth)acrylate, 1,6-hexanediol mono(meth)acrylate, glycerin mono(meth)acrylate, 2-hydroxy-3-chloropropyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-hydroxy-3-allyloxypropyl (meth)acrylate, 2-(meth)acryloyloxyethyl-2-hydroxypropyl phthalate, 2-ethylhexyl EO-modified (meth)acrylate, o-phenylphenol EO-modified acrylate, p-cumylphenol EO-modified (meth)acrylate, and nonylphenol EO-modified (meth)acrylate.

[0030] Examples of the monofunctional halogen-containing (meth)acrylate compound include trifluoromethyl (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3-tetrafluoropropyl (meth)acrylate, 1H-hexafluoroisopropyl (meth)acrylate, 1H,1H,5H-octafluoropentyl (meth)acrylate, 1H,1H,2H,2H-heptadecafluorodecyl (meth)acrylate, 2,6-dibromo-4-butylphenyl (meth)acrylate, 2,4,6-tribromophenoxyethyl (meth)acrylate, and 2,4,6-tribromophenol 3EO (ethylene oxide) adduct (meth)acrylate.

[0031] Examples of monofunctional ether group-containing (meth)acrylate compounds include 1,3-butylene glycol methyl ether (meth)acrylate, methoxytriethylene glycol (meth)acrylate, methoxydipropylene glycol (meth)acrylate, methoxytripropylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, ethyl carbitol (meth)acrylate, 2-ethylhexyl carbitol (meth)acrylate, tetrahydrofuran (meth)acrylate, methyl methyl ether ... Furyl (meth)acrylate, cresyl polyethylene glycol (meth)acrylate, 2-(vinyloxyethoxy)ethyl (meth)acrylate, phenoxyethyl (meth)acrylate, p-nonylphenoxyethyl (meth)acrylate, p-nonylphenoxypolyethylene glycol (meth)acrylate, glycidyl (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, hexaethylene glycol monophenyl ether mono(meth)acrylate , diethylene glycol monobutyl ether acrylate, dipropylene glycol monomethyl ether (meth)acrylate, 3-methoxybutyl (meth)acrylate, methoxydiethylene glycol (meth)acrylate, methoxypropylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate (EO repeating unit number 400, 700, etc.), 2-(2-ethoxyethoxy)ethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 3-methoxy Butyl acrylate, ethoxyethyl acrylate, ethoxyethoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, alkoxylated 2-phenoxyethyl (meth)acrylate (ethoxylated 2-phenoxyethyl (meth)acrylate, propoxylated 2-phenoxyethyl (meth)acrylate, etc.), alkoxylated nonylphenyl (meth)acrylate (ethoxylated (4) nonylphenol acrylate, etc.), 2-phenoxyethyl (meth)acrylate, paracumylphenoxyethylene glycol (meth)acrylate,Alkoxy and / or phenoxy (meth)acrylates such as methylphenoxyethyl acrylate, ethoxylated succinic acid (meth)acrylate, ethoxylated tribromophenyl acrylate, and ethoxylated nonylphenyl (meth)acrylate are included.

[0032] Examples of the monofunctional carboxyl group-containing (meth)acrylate compound include β-carboxyethyl (meth)acrylate, succinic acid monoacryloyloxyethyl ester, ω-carboxypolycaprolactone mono(meth)acrylate, 2-(meth)acryloyloxyethyl hydrogen phthalate, 2-(meth)acryloyloxypropyl hydrogen phthalate, 2-(meth)acryloyloxypropyl hexahydrohydrogen phthalate, and 2-(meth)acryloyloxypropyl tetrahydrohydrogen phthalate.

[0033] Examples of other monofunctional (meth)acrylate compounds include benzyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, acryloylmorpholine, morpholinoethyl (meth)acrylate, trimethylsiloxyethyl (meth)acrylate, diphenyl-2-(meth)acryloyloxyethyl phosphate, 2-(meth)acryloyloxyethyl acid phosphate, caprolactone-modified-2-(meth)acryloyl Iloxyethyl acid phosphate, 2-hydroxy-1-(meth)acryloxy-3-methacryloxypropane, acryloxyethyl phthalate, 2-(meth)acryloyloxyethyl-2-hydroxyethyl phthalate, 2-(meth)acryloyloxypropyl phthalate, tricyclodecane monomethylol (meth)acrylate, (meth)acrylic acid dimer, diethylaminoethyl (meth)acrylate, 2-(meth)acryloyloxyethyl succinate, 2-(meth)acryloyloxyethyl Hexahydrophthalic acid, 2-ethylhexyl-diglycol (meth)acrylate, aminoethyl (meth)acrylate, ethyl carbitol acrylate, ethyl diglycol acrylate, dimethylaminoethyl acrylate benzyl chloride quaternary salt, tribromophenyl (meth)acrylate, 1,4-cyclohexanedimethanol mono(meth)acrylate, cresol (meth)acrylate, trimethylolpropane formal (meth)acrylate, neopentyl glycol (meth)acrylate Acid benzoate ester, (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl (meth)acrylate, 1-(meth)acryloylpiperidin-2-one, 2-(meth)acrylic acid-1,4-dioxaspiro[4,5]dec-2-ylmethyl, N-(meth)acryloyloxyethylhexahydrophthalimide, γ-butyrolactone (meth)acrylate, caprolactone-modified tetrahydrofurfuryl acrylate, imide acrylate, vinyl (meth)acrylate, maleimide, and the like.

[0034] Examples of the monofunctional styrene-based compound include styrene, vinyltoluene, p-hydroxystyrene, p-chlorostyrene, p-bromostyrene, p-methylstyrene, p-methoxystyrene, pt-butoxystyrene, pt-butoxycarbonylstyrene, pt-butoxycarbonyloxystyrene, 2,4-diphenyl-4-methyl-1-pentene, and divinylbenzene.

[0035] Examples of the monofunctional N-vinyl compound include N-vinylpyrrolidone, N-vinylformamide, N-vinylacetamide, N-vinyl-2-caprolactam, N-vinylcarbazole, and vinylmethyloxazolidinone.

[0036] Examples of the monofunctional arylate compound include allyl glycidyl ether, diallyl phthalate, triallyl trimellitate, and isocyanuric acid triallylate.

[0037] Examples of other monofunctional monomers include vinyl acetate, vinyl monochloroacetate, vinyl benzoate, vinyl pivalate, vinyl butyrate, vinyl laurate, divinyl adipate, vinyl crotonate, vinyl 2-ethylhexanoate, three-membered ring compounds (e.g., vinylcyclopropanes, 1-phenyl-2-vinylcyclopropanes, 2-phenyl-3-vinyloxiranes, 2,3-divinyloxiranes, etc.), cyclic ketene acetals (e.g., 2-methylene-1,3-dioxepane, dioxolanes, 2-methylene-4-phenyl-1,3-dioxepane, 4,7-dimethyl-2-methylene-1,3-dioxepane, 5,6-benzo-2-methylene-1,3-dioxepane, etc.), and the like.

[0038] The monofunctional photopolymerizable monomer contained in the ultraviolet ray shielding ink composition is preferably a monomer with reduced odor. This is because the ultraviolet ray shielding ink composition is semi-cured upon light irradiation, but is not completely cured. Preferred examples of the monofunctional photopolymerizable monomer include acryloylmorpholine, N-vinylcaprolactam, and 4-hydroxybutyl acrylate.

[0039] [1-1-3. Photopolymerizable monomers with a glass transition temperature of 60°C or higher] Some or all of the photopolymerizable monomers contained in the UV-blocking ink composition are photopolymerizable monomers having a glass transition temperature of 60° C. or higher. The photopolymerizable monomers having a glass transition temperature of 60° C. or higher preferably include a photopolymerizable monomer having a glass transition temperature of 80° C. or higher, more preferably a photopolymerizable monomer having a glass transition temperature of 90° C. or higher, and even more preferably a photopolymerizable monomer having a glass transition temperature of 100° C. or higher. A photopolymerizable monomer having a glass transition temperature of 60° C. or higher means that the glass transition temperature of the photopolymerizable monomer when made into a homopolymer is 60° C. or higher.

[0040] The photopolymerizable monomer having a glass transition temperature of 60°C or higher may be a polyfunctional monomer or a monofunctional monomer; however, it usually contains a polyfunctional monomer having a glass transition temperature of 60°C or higher, or contains a combination of a polyfunctional monomer and a monofunctional monomer, both of which have a glass transition temperature of 60°C or higher.

[0041] Examples of polyfunctional monomers having a glass transition temperature Tg of 60°C or higher include tripropylene glycol diacrylate (62°C), dipropylene glycol diacrylate (102°C), 1,3-butylene glycol diacrylate (101°C), diethylene glycol diacrylate (100°C), ethoxylated (3) bisphenol A diacrylate (67°C), diethylene glycol dimethacrylate (66°C), ethoxylated bisphenol A dimethacrylate (108°C), and the like.

[0042] Examples of monofunctional monomers having a glass transition temperature Tg of 60°C or higher include acryloylmorpholine (145°C), isobornyl acrylate (97°C), dicyclopentenyl-A (120°C), dicyclopentanyl-A (120°C), N,N-dimethylacrylamide (119°C), vinylmethyloxazolidinone (120°C), and the like.

[0043] [1-1-4. Photopolymerizable monomer content and composition] The content of the photopolymerizable monomer in the ultraviolet ray shielding ink composition of the present invention is 65.0% by mass or more, preferably 70.0% by mass or more, more preferably 75.0% by mass or more, and may be 85.0% by mass or more; on the other hand, it is usually less than 95.0% by mass, preferably 94% by mass or less. By making the content of the photopolymerizable monomer 65.0% by mass or more, the ink composition can be easily ejected, and the printed layer of the ultraviolet ray shielding ink composition can be solidified by polymerization of the photopolymerizable monomer upon irradiation with ultraviolet rays.

[0044] The UV-shielding ink composition of the present invention contains a photopolymerizable monomer, but preferably contains at least a polyfunctional monomer, and a polyfunctional monomer may be combined with a monofunctional monomer. More specifically, the photopolymerizable monomers preferably account for 50.0% by mass or more of the photopolymerizable monomers, more preferably 55.0% by mass or more, and all of the photopolymerizable monomers may be polyfunctional monomers. When the photopolymerizable monomers account for 50.0% by mass or more of the polyfunctional monomers, polymerization and solidification are facilitated by irradiating the printed layer of the UV-shielding ink composition with UV rays. If the proportion of the polyfunctional monomer is too low, the surface layer of the printed layer will solidify, but the inner layer of the printed layer may not solidify and may remain liquid.

[0045] Furthermore, some or all of the photopolymerizable monomers contained in the ultraviolet ray shielding ink composition of the present invention are photopolymerizable monomers having a glass transition temperature of 60°C or higher; however, the content ratio of the photopolymerizable monomers having a glass transition temperature of 60°C or higher in the ultraviolet ray shielding ink composition is related to the composition of the non-polymerizable material, and will be described later.

[0046] [1-2. Non-polymerizable material] The UV-shielding ink composition of the present invention contains a non-polymerizable material in addition to a photopolymerizable monomer and a UV absorber. When the UV-shielding ink composition contains a non-polymerizable material, the hardness of the ink composition solidified by polymerization of the photopolymerizable monomer can be reduced, and preferably, the solidified ink composition can be made "brittle." This makes it easier to remove or peel the solidified printing layer from the printed substrate. Examples of non-polymerizable materials include non-polymerizable polymer compounds and non-polymerizable low-molecular-weight compounds, and preferably contain a non-polymerizable polymer compound, or may contain a combination of a non-polymerizable polymer compound and a non-polymerizable low-molecular-weight compound.

[0047] [1-2-1. Polymer compounds as non-polymeric materials] The polymer compound as the non-polymerizable material preferably does not have a crosslinking group or the like and does not react with other components of the UV-blocking ink composition (particularly the photopolymerizable monomer.) The polymer compound as the non-polymerizable material is preferably a thermoplastic resin, such as poly(meth)acrylic acid, poly(meth)acrylic acid ester, polyethylacrylic acid, styrene-butadiene copolymer, polybutadiene, acrylonitrile-butadiene copolymer, chloroprene copolymer, fluororesin, vinylidene fluoride, polyolefin resin, cellulose, styrene-acrylic acid copolymer, styrene-methacrylic acid copolymer, polystyrene, styrene-acrylamide copolymer, polyisobutyl acrylate, polyacrylonitrile, polyvinyl acetate, polyvinyl acetal, polyamide, rosin resin, polyethylene, polycarbonate, vinylidene chloride resin, cellulose resin, vinyl acetate resin, ethylene-vinyl acetate copolymer, vinyl acetate-acrylic copolymer, vinyl chloride resin, polyurethane, and rosin ester. Specific examples of relatively low molecular weight thermoplastic resins include polyethylene wax, montan wax, alcohol wax, synthetic oxide wax, α-olefin-maleic anhydride copolymer, animal and vegetable waxes such as carnauba wax, lanolin, paraffin wax, microcrystalline wax, etc. These polymer compounds are preferably contained in the ultraviolet ray blocking ink composition as resin particles.

[0048] A preferred example of a polymer compound as a non-polymerizable material includes a poly(meth)acrylic acid ester, and the polymer compound is preferably contained in the ultraviolet ray blocking ink composition as particles thereof.

[0049] [1-2-2. Low molecular weight compounds as non-polymerizable materials] The low molecular weight compound as the non-polymerizable material is preferably a low molecular weight compound that does not react with other components of the ultraviolet ray blocking ink composition, and suitable examples thereof include 1) a substance having sublimation properties (sublimable substance) and 2) terpenes.

[0050] Sublimable substances include alizarin, alloxan, amantadine, (3α,5α)-androst-16-en-3-ol, anthraquinone, caffeine, chloranil, chloroacetamide, p-dichlorobenzene, emodin, homoeriodictyol, cubane, cysteamine, esculetin, guanine, hexachloroethane, isatin, lumiflavin, maleic anhydride, 1,4-naphthoquinone, nimbiol, phenazine, phthalimide, 2,5-piperazinedione, 1H-purine, purpurine, pyrene, Mordant Violet 26 (Quinalizarin), p-benzoquinone, saccharin, solasodine, succinic anhydride, thebaine, xanthine, and camphor.

[0051] Examples of terpenes include monoterpene hydrocarbons such as α-pinene, β-pinene, dipentene, limonene, turpentine, phellandrene, α-terpinene, γ-terpinene, terpinolene, myrcene, alloocimene, camphene, bornylene, paramenthene-1, paramenthene-2, paramenthene-3, paramentadiene, paramenthane, 2-carene, 3-carene, and thujane; and α-terpineol, β-terpineol, γ-terpineol, 4-terpineol, paramenthenol, paramentanol, geraniol, linalool, nerol, citronellol, allocimenol, and myrcenol. monoterpene alcohols such as carveol, L-menthol, borneol, isoborneol, fenchyl alcohol, and verbenol; terpene aldehydes such as citral and citronellal; terpene ketones such as isopulegone, carvone, and camphor (camphor white oil); terpene diols such as paramenthanediol; terpene ethers such as 1,4-cineole and 1,8-cineole; sesquiterpene hydrocarbons such as longifolene, caryophyllene, cadinene, thujopsene, cedrene, clobene, and longipinene; and sesquiterpene alcohols such as elemol, cadinol, and eudesmol.

[0052] It may be preferable that the ultraviolet light-shielding ink composition contains L-menthol, which is a low molecular weight compound, as a non-polymerizable material.

[0053] [1-2-3. Non-polymerizable materials with a glass transition temperature of 60°C or higher] A part or all of the non-polymerizable materials contained in the ultraviolet ray blocking ink composition are non-polymerizable materials having a glass transition temperature of 60° C. or higher. The non-polymerizable materials having a glass transition temperature of 60° C. or higher preferably include a non-polymerizable material having a glass transition temperature of 80° C. or higher, more preferably a non-polymerizable material having a glass transition temperature of 90° C. or higher, and even more preferably a non-polymerizable material having a glass transition temperature of 100° C. or higher.

[0054] Examples of non-polymeric materials having a glass transition temperature of 60° C. or higher may be commercially available products. For example, DEGALANR LP 62 / 05 (60℃), DEGALANR LP 64 / 12 (63℃), DEGALANR P 26 (66℃), DEGALANR LP 66 / 02N (70℃), DEGALANR LP 66 / 02 (82℃), DEGALANR LP 67 / 11 (85℃), DEGALANR LP 53 / 13C(102℃), DEGALANR M 345(104℃), DEGALANR M 748(105℃), DEGALANR M 810(104℃), DEGALANR M 825(105℃), DEGALANR LP 50 / 01(109℃), DEGALANR LP 50 / 02(116℃), DEGALANR LP 51 / 03 (118°C), DEGALANR M 920 (122°C) (Rohm Co., Ltd.); DIANAL BR-50 (108°C), DIANAL BR-73 (97°C), DIANAL BR-83 (105°C), DIANAL BR-113 (75°C), DIANAL BR-119 (83°C), DIANAL BR-605 (60°C), DIANAL MB-2660 (63°C), DIANAL MB-2952 (85°C) (Mitsubishi Chemical Corporation), etc.

[0055] [1-2-4. Content and composition of non-polymerizable materials] The content of the non-polymerizable material in the UV-shielding ink composition is preferably set so as to impart "brittleness" to the solidified product when the UV-shielding ink composition is solidified by UV irradiation. Therefore, the UV-shielding ink composition contains 5.0% by mass or more of the non-polymerizable material; while the content is less than 20.0% by mass, preferably 15.0% by mass or less, and more preferably 11% by mass or less. If the content of the non-polymerizable material is too high, the viscosity of the UV-shielding ink composition may increase or some of the non-polymerizable material may become insoluble in the ink composition, resulting in unstable inkjet printing (reduced ejection stability).

[0056] The UV-shielding ink composition contains a photopolymerizable monomer having a glass transition temperature of 60° C. or higher and a non-polymerizable material having a glass transition temperature of 60° C. or higher; the total content of these is preferably 20% by mass or higher, and more preferably 25% by mass or higher, based on the UV-shielding ink composition. By ensuring that the total content is 20% by mass or higher, it is possible to reduce the stickiness of the cured (semi-cured) product of the ink composition after light irradiation, making it easier to remove the cured (semi-cured) product.

[0057] [1-3. UV absorbers] The UV-blocking ink composition of the present invention contains an UV absorber. By absorbing UV rays, the UV absorber 1) prevents the photopolymerizable monomer in the UV-blocking ink composition from becoming excessively excited, and 2) prevents some of the UV rays from reaching the underlayer in the area where the UV-blocking ink composition is printed. Therefore, upon UV irradiation, the printed layer of the UV-blocking ink composition polymerizes and solidifies, while preventing the underlayer, which is a photocurable resin, from being completely cured, leaving it in a semi-cured state.

[0058] Ultraviolet absorbers are generally classified into benzotriazole (BTZ)-based ultraviolet absorbers, hydroxyphenyltriazine (HPT)-based ultraviolet absorbers, salicylic acid-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, cyanoacrylate-based ultraviolet absorbers, polymer-based ultraviolet absorbers, and the like; the ultraviolet shading ink composition of the present invention may contain any type of ultraviolet absorber, or may contain one or more types of ultraviolet absorbers.

[0059] Examples of the benzotriazole (BTZ) ultraviolet absorber include 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2-hydroxy-5-t-butylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-t-butylphenyl)benzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)benzotriazole, 2-(3,5-di-t-pentyl-2-hydroxyphenyl)benzotriazole, 2-(2-benzotriazol-2-yl)-4-methyl-6-(3,4,5,6-tetrahydrophthalimidylmethyl)phenol, 2-(2-hydroxy-4-octyloxyphenyl)-2-benzotriazole, and 2-(2-hydroxy-5-t-octylphenyl)-2-benzotriazole. Benzotriazole (BTZ)-based UV absorbers are also commercially available, and examples thereof include Sumisorb 200, Sumisorb 250, Sumisorb 300, Sumisorb 340, and Sumisorb 350 (Sumitomo Chemical Co., Ltd.), TINUVIN PS, TINUVIN 99-2, TINUVIN 234, TINUVIN 320, TINUVIN 326, TINUVIN 328, TINUVIN 329, TINUVIN 384, TINUVIN 384-2, TINUVIN 571, TINUVIN 900, TINUVIN 928, and TINUVIN 1130 (BASF), Adeka STAB LA-32, Adeka STAB LA-29, Adeka STAB LA-31, Adeka STAB LA-31RG, Adeka STAB LA-31G, Adeka STAB LA-36, and Adeka STAB LA-37. They are available as LA-36RG (ADEKA), and SEESORB 701, SEESORB 703, SEESORB 704, SEESORB 706, SEESORB 707, and SEESORB 709 (Shipro Kasei), etc.

[0060] Examples of hydroxyphenyltriazine (HPT) ultraviolet absorbers include 2,4-diphenyl-6-(2-hydroxy-4-methoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-ethoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-(2-hydroxy-4-propoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-(2-hydroxy-4-butoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-butoxyphenyl)-1,3,5-triazine, 2-(2-hydroxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-hexyloxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-dodecyloxyphenyl)-1,3,5-triazine, and 2,4-diphenyl-6-(2-hydroxy-4-benzyloxyphenyl)-1,3,5-triazine. Hydroxyphenyltriazine (HPT)-based ultraviolet absorbers are also commercially available, such as TINUVIN 400, TINUVIN 405, TINUVIN 460, TINUVIN 477, TINUVIN 479, TINUVIN 777, and TINUVIN 1577ED (BASF), and Adeka STAB LA-F70 (ADEKA).

[0061] Examples of salicylic acid-based UV absorbers include phenyl salicylate, pt-butylphenyl salicylate, 2-4-di-t-butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate, etc. Salicylic acid-based UV absorbers are also commercially available, such as Sumisorb 400 (Sumitomo Chemical Co., Ltd.), and SEESORB 201, SEESORB 202, and SEESORB 712 (Shipro Chemical Co., Ltd.).

[0062] Examples of the benzophenone-based ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4-methoxy-benzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2-hydroxy-4-octadecyloxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, and 1,4-bis(4-benzoyl-3-hydroxyphenoxy)butane. Benzophenone-based ultraviolet absorbers are also commercially available, and include Sumisorb 130 (Sumitomo Chemical Co., Ltd.), Adekastab 1413 (ADEKA Corporation), and Seesorb 100, Seesorb 101, Seesorb 106, Seesorb 107, Seesorb 101S, Seesorb 102, Seesorb 103, Seesorb 105, and Seesorb 151 (Shipro Chemical Co., Ltd.).

[0063] Examples of cyanoacrylate-based UV absorbers include ethyl-2-cyano-3,3-diphenylacrylate, 2-ethylhexyl 2-cyano-3,3-diphenylacrylate, etc. Commercially available cyanoacrylate-based UV absorbers include SEESORB 501, SEESORB 502 (Shipro Chemicals), Uvinul 3039, Uvinul 3035 (BASF), etc.

[0064] The polymeric ultraviolet absorber may be a copolymer of an acrylic monomer having a skeleton acting as an ultraviolet absorber (such as the aforementioned benzophenone, benzotriazole, or triazine) in its side chain and another ethylenically unsaturated compound (such as acrylic acid, methacrylic acid, or derivatives thereof, styrene, or vinyl acetate). Examples of the polymeric ultraviolet absorber include polymeric ultraviolet absorbers for coating such as ULS-700, ULS-1700, ULS-383MA, ULS-1383MA, ULS-383MG, ULS-385MG, ULS-1383MG, ULS-1385MG, ULS-635MH, ULS-933LP, ULS-935LH, ULS-1935LH, HC-935UE, XL-504, XL-524, XL-547, XL-729, and XL-730 (Ipposha Oils and Fats Industries Co., Ltd.), and polymeric ultraviolet-absorbing resin paints NCI-905-20EM and NCI-905-20EMA (polymeric ultraviolet absorbers made of copolymers of styrene monomers and benzotriazole-based monomers) (Nikko Chemical Research Institute Co., Ltd.).

[0065] The content of the ultraviolet absorber in the ultraviolet ray blocking ink composition of the present invention is 0.5% by mass or more, preferably 0.7% by mass or more, and more preferably 1.0% by mass or more; and on the other hand, it is less than 3.0% by mass, preferably 2.8% by mass or less, and more preferably 2.5% by mass or less. When the content of the ultraviolet absorber is 0.5% by mass or more, the ultraviolet ray blocking ability is sufficient, and excessive polymerization of the ultraviolet ray blocking ink composition itself and ultraviolet irradiation of the underlying layer of the printed layer of the ultraviolet ray blocking ink composition are appropriately suppressed. On the other hand, when the content of the ultraviolet absorber is less than 3.0% by mass, ultraviolet rays are appropriately irradiated onto the underlying layer through the printed layer of the ultraviolet ray blocking ink composition, allowing the underlying layer to solidify in a semi-cured state.

[0066] In the ultraviolet light-shielding ink composition of the present invention, the content of the ultraviolet absorber is set to a low level, which promotes curing while reducing the adhesiveness of the cured product (semi-cured product), thereby facilitating removal of the cured product (semi-cured product) and improving workability. On the other hand, if the content of the ultraviolet absorber is set to a high level and the degree of curing is suppressed, the hardness of the cured product (semi-cured product) decreases, and although removal of the cured product (semi-cured product) itself is possible, the adhesiveness of the cured product (semi-cured product) increases, which can sometimes reduce the workability of removal.

[0067] The ultraviolet absorber in the ultraviolet shielding ink composition of the present invention is distinguished from a light stabilizer. A light stabilizer is an agent that eliminates radicals generated by irradiation with ultraviolet light, and is different from ultraviolet absorbers, which suppress the generation of radicals themselves. The ultraviolet shielding ink composition of the present invention contains at least an ultraviolet absorber, and may also contain a light stabilizer together with the ultraviolet absorber.

[0068] Examples of the light stabilizer include hindered amine compounds (HALS: Hindered Amine Light Stabilizer); specifically, 4-perzoyloxy-2,2,6,6-tetramethylpiperidine, bis-(2,2,6,6-tetramethyl-4-piperidyl)malonate, bis-(2,2,6,6-tetramethyl-4-piperidyl)phthalate, (2,2,6,6-tetramethyl-4-piperidylbenzoate, 4-amino-2,2,6,6-tetramethyl-piperidine, 2,2,6,6-tetramethyl-4-piperidine)sepacate, bis-(2,2,6,6-tetramethyl-4-methylpiperidyl)sepacate, di-(1,2,2,6,6-pentamethyl-4-piperidyl)-2-n-butyl-2-(3,5-di-t-butyl-4-hydroxybenzyl)malonate, bis- These include (2,2,6,6-tetramethyl-4-carbonyloxypiperidino)-p-dimethylbenzyl, 2,2,4,4-tetramethyl-7-oxa-3,20-diaza-21-oxo-disbilo[5·1·9·19]heneicone, bis-(2,2,6,6-tetramethyl-4-piperidinyl)sebacate, dimethyl succinate, 2-(4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyl)ethynol condensate, [(6-(1,1,3,3-tetramethylbutyl)imino)-1,3,5-triazine-2,4-diyl-(4-(2,2,6,6-tetramethylpiperidinyl)imino)-hexamethylene-(4-(2,2,6,6-tetramethylpiperidinyl)imino)].

[0069] [1-4. Other ingredients] The UV-shielding ink composition of the present invention may contain a surface conditioner for adjusting surface tension. As described below, a high surface tension is sometimes preferable for the UV-shielding ink composition, and therefore the ink composition may contain a surface conditioner that increases the surface tension. Examples of surface conditioners that increase the surface tension include amine compounds, polyether macromer-modified polyacrylate (available as BYK3560 (BYK-Chemie)), and polyether silicone macromer-modified polyacrylate (available as BYK3565 (BYK-Chemie)). When the UV-shielding ink composition contains a surface conditioner, the content thereof is preferably in the range of 0.01 to 1.0 mass %.

[0070] The ink composition for UV protection of the present invention may contain a colorant (preferably a dye). This is to make the area printed with the ink composition for UV protection more visible and to make it easier to identify the area to be removed. When the ink composition for UV protection contains a dye, the content thereof is preferably in the range of 0.01 to 2.0% by mass.

[0071] The ultraviolet ray shielding ink composition of the present invention usually does not contain a solvent; however, if viscosity adjustment or the like is required, it may contain a small amount (for example, 5% by mass or less of the ink composition) of an organic solvent.

[0072] [1-5. Physical properties of UV-shielding ink composition] The ultraviolet light-shielding ink composition of the present invention is printed by an inkjet method, and therefore its viscosity (25°C) is preferably 10 cps or more, more preferably 12 cps or more, and is preferably about 30 cps or less, more preferably less than 24 cps. The viscosity is measured, for example, with an E-type viscometer (25°C, rotor rotation speed 10 rpm).

[0073] The UV-blocking ink composition of the present invention may be printed on a liquid film or layer (underlayer). The compatibility of the UV-blocking ink composition of the present invention with a liquid film or layer can be adjusted by adjusting its surface tension. That is, the higher the surface tension of the UV-blocking ink composition, the lower the compatibility with the liquid film or layer, and the less likely it is to mix with the liquid film or layer (underlayer); the lower the surface tension of the UV-blocking ink composition, the more compatible it is. It is preferable to adjust the surface tension of the UV-blocking ink composition of the present invention printed on a liquid film or layer (underlayer) so that it is compatible to a certain extent.

[0074] When an ultraviolet light-shielding ink composition contains a photopolymerizable monomer having a polar group (a hydroxy group, an amino group, an aromatic group, or the like), the surface tension of the composition is usually likely to increase.

[0075] [1-6. Production of UV-shielding ink composition] The ultraviolet ray shielding ink composition of the present invention can be produced by any method, for example, by adding and mixing a non-polymerizable material into a photopolymerizable monomer, preferably dissolving it, and then further mixing an ultraviolet ray absorber and other components thereinto to obtain the ultraviolet ray shielding ink composition.

[0076] [2. Method for manufacturing a substrate having an embossed surface] The method for producing a substrate having an embossed surface of the present invention includes: 1) a coating step of applying a composition containing a photopolymerizable compound to the surface of the substrate to form a coating film; 2) a printing step of inkjet-printing an ultraviolet ray blocking ink composition onto the uncured coating film containing the photopolymerizable compound that has been coated on the substrate; 3) an irradiation step of irradiating ultraviolet rays onto the coating film printed with the ultraviolet ray blocking ink composition; and 4) a removal step of removing the coating film in the area printed with the ultraviolet ray blocking ink composition; and may further include a finishing step, such as 5) forming another layer on the surface of the embossed structure.

[0077] Hereinafter, a method for producing a substrate having an embossed surface will be described with reference to FIG.

[0078] [2-1. Coating process] The coating step is a step of coating the surface of the substrate (1) with a coating film (2-1) (see FIG. 1(a)). The substrate (1) may be any member on whose surface an embossed structure is to be formed, and its material is not particularly limited; it may be made of plastics, metal, wood, paper, cement, gypsum, rock, glass, ceramic, or the like. In addition, it may be preferable that the surface of the substrate on which an embossed structure is to be formed is subjected to a surface treatment to enhance wettability. This is to make it easier to coat the surface of the substrate with a coating film.

[0079] [2-1-1. Photocurable resin composition to be coated] The coating film (2-1) coated on the surface of the substrate (1) is preferably made of a photocurable resin composition. The photocurable resin composition contains a photopolymerizable compound (preferably a photocurable monomer or oligomer), and preferably further contains a photopolymerization initiator, and may also contain a filler and a surface conditioner.

[0080] The photopolymerizable compound contained in the photocurable resin composition is preferably a photocurable resin, and examples thereof include photocurable diallyl phthalate resin, epoxy resin, unsaturated polyester resin, polyurethane resin, acrylic resin, etc. Particularly, examples of radically polymerizable resins include diallyl phthalate resin, vinyl monomer, or acrylic resin (acrylate monomer, epoxy acrylate, urethane acrylate, polyester acrylate, polyether acrylate, amino acrylate, silicone acrylate, polyisoprene acrylate, polybutadiene acrylate), etc. The content of the photopolymerizable compound in the photocurable resin composition is approximately 70% by mass or more, preferably 75% by mass or more; and approximately 95% by mass or less, more preferably 90% by mass or less.

[0081] The photocurable resin composition may contain one or more photopolymerization initiators. Examples of photopolymerization initiators include benzophenone, diethylthioxanthone, 2-methyl-1-(4-methylthio)phenyl-2-morpholinopropan-1-one, 4-benzoyl-4'-methyldiphenyl sulfide, 1-chloro-4-propoxythioxanthone, isopropylthioxanthone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, bis-2,6-dimethoxybenzoyl-2 ,4,4-trimethylpentylphosphine oxide, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2,2-dimethyl-2-hydroxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,4,6-trimethylbenzyl-diphenylphosphine oxide, 2-benzyl-2-dimethylamino-1-(morpholinophenyl)-butan-1-one, etc. Such photopolymerization initiators can also be obtained commercially, for example, under the trade names Irgacure 907, Irgacure 369, Irgacure 184, Irgacure 379, Irgacure 819 (all from BASF), DETX (from Lamberti), etc.

[0082] The content of the photopolymerization initiator in the photocurable resin composition to be coated may be set depending on the desired curing speed of the photocurable resin composition, but as a guideline, it is preferably 1% by mass or more, more preferably 3% by mass or more; and preferably 10% by mass or less, more preferably 7% by mass or less.

[0083] The photocurable resin composition preferably has a low surface tension; therefore, it may contain a surface conditioner for lowering the surface tension. Such a surface conditioner improves the leveling and slipping properties of the photocurable resin composition. Examples of surface conditioners include silicone-based surface conditioners, fluorine-based surface conditioners, acrylic-based surface conditioners, and acetylene glycol-based surface conditioners. Specific examples of surface conditioners for lowering surface tension include the BYK series (BYK377, etc.) manufactured by BYK-Chemie, the TEGO series manufactured by EVONIK, and the Polyflow series manufactured by Kyoeisha Chemical Co., Ltd. When the photocurable resin composition contains a surface conditioner, the content thereof is preferably in the range of 0.01 to 1.0% by mass.

[0084] By adding a filler to the photocurable resin composition, the physical properties (hardness, etc.) of the cured product can be adjusted. For example, aluminum oxide or the like can be added to improve the abrasion resistance of the cured product, talc can be added to adjust the deformability (rheology), silica can be added to reduce brittleness, calcium carbonate can be added as an extender, and a colorant can be added to color the cured product. Furthermore, by adding a thixotropic agent to the photocurable resin composition, the shape of the uncured coating film can be more easily maintained, and an embossed structure of the desired shape can be more easily formed.

[0085] The photocurable resin composition may contain a matting agent, which is an agent for finely roughening (also called matte finishing) the surface of the cured product; examples of matting agents include resin beads and inorganic beads such as silica and aluminum oxide beads.

[0086] Furthermore, photocurable resin compositions generally do not contain a solvent (a component that is removed after curing); however, they may contain a small amount of solvent for the purpose of obtaining coating properties, etc.

[0087] [2-1-2. Coating film] The thickness of the coating film (2-1) coated on the surface of the substrate (1) can be set according to the shape of the embossed surface to be formed, and the thicker the coating film (2-1), the more uneven the embossed surface can be formed. The thickness of the coating film (2-1) can be 30 μm or more, 100 μm or more, or even about 200 μm. The upper limit of the thickness of the coating film (2-1) is appropriately set depending on the application of the substrate having an embossed surface to be produced.

[0088] The photocurable resin composition constituting the coating film (2-1) is preferably completely photocured to give a cured product (2-2) having a pencil hardness of 2H or more. The specific hardness of the cured product (2-2) may be adjusted depending on the application of the substrate having an embossed surface to be produced.

[0089] [2-2.Printing process] The printing step is a step of inkjet printing an ultraviolet ray blocking ink composition (3-1) onto a coating film (2-1) formed on the surface of a substrate (1) (see FIG. 1(b)). The ultraviolet ray blocking ink composition is preferably the same as that described above in [1. Ink composition for ultraviolet ray blocking].

[0090] The inkjet printing method is not particularly limited. For example, the inkjet printing method may be either a multi-pass mode (serial head mode) or a single-pass mode (line head mode).

[0091] The areas where the ultraviolet ray blocking ink composition is printed become the recesses of the embossed shape to be formed, so printing can be performed according to the desired embossed shape. The amount of ultraviolet ray blocking ink composition applied for printing per unit area should be an amount that can completely cover the desired printing area and that will cause the coating film (2-1) in the area where the ultraviolet ray blocking ink composition (3-1) is printed to be in a semi-cured state. If the amount of printing application per unit area is large, the curing reaction of the coating film (2-1) will not proceed easily; if it is small, the curing reaction will proceed easily.

[0092] [2-3. Irradiation process] The irradiation step is a step of irradiating ultraviolet light onto the coating film (2-1) printed with the ultraviolet light blocking ink composition (3-1) (see FIG. 1(c)). The exposure machine (4) for irradiating ultraviolet light is not particularly limited as long as it can irradiate ultraviolet light at a predetermined exposure dose. However, considering productivity, it is preferable that the exposure machine be capable of irradiating a predetermined amount of ultraviolet light in a short time. The areas of the coating film (2-1) where the ultraviolet light blocking ink composition (3-1) is not printed are directly irradiated with ultraviolet light, so photocuring proceeds sufficiently to form a completely cured product (2-2). On the other hand, the areas of the coating film (2-1) where the ultraviolet light blocking ink composition (3-1) is printed are irradiated with ultraviolet light through the printed layer of the ultraviolet light blocking ink composition (3-1). Therefore, photocuring does not proceed completely, but the coating film solidifies to form a semi-cured product (2-3). Furthermore, the ultraviolet light blocking ink composition (3-1) also becomes a cured product (3-2) when irradiated with ultraviolet light. In addition, although the semi-cured product (2-3) and the cured product (3-2) are shown as completely separate layers in FIG. 1, they may be mixed near the interface, or may be completely compatible and integrated.

[0093] The amount of UV light irradiated onto the coating film should be sufficient to completely cure the coating film (2-1) into a completely cured product (2-2); however, excessive UV light exposure may accelerate photocuring of the semi-cured product (2-3), potentially resulting in a completely cured product. Therefore, it is preferable that the amount of UV light exposure be an amount necessary and sufficient to completely cure the coating film (2-1) in the area without the printed layer of UV-shielding ink composition (3-1) into a completely cured product (2-2). In other words, the amount of UV light exposure is appropriately set depending on the ease of photocuring the UV-shielding ink composition (3-1) and the amount of UV-shielding ink composition (3-1) printed.

[0094] The hardness of the cured product (2-2) of the coating film (2-1) varies depending on the application of the embossed material, but is usually preferably a pencil hardness of 2H or more. On the other hand, the hardness of the semi-cured product (2-3) of the coating film (2-1) may be lower than the hardness of the cured product (2-2). In other words, the hardness of the semi-cured product (2-3) may be less than 2H pencil hardness, but may be higher depending on the hardness of the cured product (2-2). In other words, a) if the hardness of the cured product (2-2) is high, the hardness of the semi-cured product (2-3) may also be high, and b) if the removal ability (peelability) of the removal means in the following removal step is high, the hardness of the semi-cured product (2-3) may also be high.

[0095] [2-4. Removal process] The removal step is a step of removing the semi-cured product (2-3) and the cured product (3-2) formed in the irradiation step (see FIG. 1(d)). As mentioned above, the semi-cured product (2-3) and the cured product (3-2) may not be completely separate layers, but may be mixed near the interface, or may be completely dissolved and integrated. On the other hand, the cured product (2-2) of the coating film (2-1) is not removed in the removal step due to its high hardness. These are removed mechanically, preferably by rubbing a brush (5) or pad against the coating film. The material of the brush (5) or pad may be, for example, steel, brass, nylon fiber, polyester fiber, etc., but is not particularly limited. Alternatively, the semi-cured product (2-3) and the cured product (3-2) may be removed using a high-pressure air jet or high-pressure water jet, or by peeling them off with an adhesive roller or adhesive tape.

[0096] In the ultraviolet ray shielding ink composition, the content of the ultraviolet absorber is set to a certain level or less, and the content of the component having a glass transition temperature of 60°C or higher is set to a certain level or more, so that the curing of the cured product (3-2) proceeds easily and the tackiness thereof is reduced. Furthermore, although the curing of the semi-cured product (2-3) does not proceed completely due to the light shielding of the cured product (3-2), some of the components having a glass transition temperature of 60°C or higher contained in the ultraviolet ray shielding ink composition are compatible with the semi-cured product (2-3), which may reduce the tackiness of the semi-cured product (2-3).

[0097] In this way, by reducing the adhesiveness of the semi-cured product (2-3) and the cured product (3-2) to be removed, removal can be facilitated and workability can be improved. For example, when the removal step is performed by rubbing with a brush (5) or pad, it is possible to prevent less adhesive removal components from adhering to the brush (5) or pad. Furthermore, when the removal step is performed with a high-pressure air jet or high-pressure water jet, less adhesive removal components can be easily removed.

[0098] By removing the semi-cured product (2-3) and the cured product (3-2), the removed portions become recesses, and an embossed structure is formed on the surface of the substrate (1).

[0099] [2-5. Finishing process] An optional coating layer (6) may be applied to the embossed structure formed on the surface of the substrate (1) to impart weather resistance, abrasion resistance, wear resistance, and solvent resistance (see FIG. 1(e)). Furthermore, the desired appearance (brightness, luminance, saturation, etc.) can be adjusted by applying a varnish coating, etc. Any other optional finishing treatments can be performed.

[0100] The article thus produced, having an embossed shape formed thereon, can be used as a decorative board for any building material (flooring, walling, flooring, etc.), baseboard, furniture, etc. [Example]

[0101] The present invention will be described below with reference to examples, but the present invention should not be construed as being limited to these examples.

[0102] [A. Preparation of UV-Shielding Ink Composition] The materials used in preparing the ultraviolet light-shielding ink composition are shown below.

[0103] [A-1. Photopolymerizable Monomer] 1,6-Hexanediol diacrylate: Glass transition temperature 40℃ Neopentyl glycol PO-modified diacrylate ((PO)NPGDA) (Miramer M216 (Toyo Chemicals Co., Ltd.)): Glass transition temperature 32°C Tripropylene glycol diacrylate: Glass transition temperature 62°C Dipropylene glycol diacrylate: Glass transition temperature 102°C Acryloylmorpholine: Glass transition temperature 145℃ Lauryl acrylate: Glass transition temperature -23°C

[0104] [A-2. Non-polymerizable material] Acrylic polymer: DEGALAN LP 66 / 02N (ROHM Co., Ltd.) Glass transition temperature 70°C, molecular weight (DIN standard) 60,000 Acrylic polymer: Dianal BR-83 (Mitsubishi Chemical Corporation) Glass transition temperature 105°C, weight average molecular weight 40,000 Acrylic polymer: DEGALAN PM381N (ROHM Co., Ltd.), glass transition temperature 57°C, weight average molecular weight 65,000 L-Menthol (Kishida Chemical Co., Ltd.)

[0105] [A-3. UV absorbers, etc.] Hydroxyphenyltriazine (HPT) UV absorber: TINUVIN 400 (BASF)

[0106] [ka]

[0107] [A-4. Preparation process of ultraviolet light-shielding ink composition] Photopolymerizable monomers, non-polymerizable materials, and ultraviolet absorbers or light stabilizers were mixed according to the formulations shown in Tables 2 and 3 (the numerical values ​​in the formulations indicate parts by mass), to obtain ultraviolet-shielding ink compositions of Examples 1 to 9 and Comparative Examples 1 to 7. The acrylic polymers (DEGALAN LP 66 / 02N, DIANAL BR-83, DEGALAN PM381N), which are non-polymerizable materials, were dissolved by heating in the photopolymerizable monomers and then mixed with the other materials.

[0108] B. Preparation of a Substrate Having an Embossed Surface MDF (medium density fiberboard) was prepared as the substrate; a photocurable resin composition with the composition shown in Table 1 was applied to the surface of the substrate using a roll coater to form a coating film (50 μm thick). The prepared UV-blocking ink composition was then inkjet-printed onto the (uncured) coating film. A Ricoh GEN6 UV inkjet ink print evaluation device (300 dpi, droplet volume (5 pL-50 pL)) was used to print characters consisting of lines 2 mm wide. The inkjet-printed ink composition was printed in a single pass, 80-100% solid coverage, to completely cover the area to be printed. After printing, 100 mJ / cm 2 The resin surface after hardening was brushed with a plastic brush to peel off and remove the resin from the printed area.

[0109] [Table 1]

[0110] [C. Evaluation] [C-1. Viscosity of UV-shielding ink composition] The viscosity (cps) of the ink compositions obtained in each of the examples and comparative examples was measured using an E-type viscometer (product name: RE100L type viscometer, manufactured by Toki Sangyo Co., Ltd.) at a temperature of 25°C and a rotor rotation speed of 10 rpm.

[0111] [C-2. Embossing suitability: peelability] The workability and peeling state of the brushing were evaluated according to the following criteria. ◎: Only the printed part was easily and cleanly scraped off 〇: Only the printed part was scraped off cleanly △: Some of the printed area could not be scraped off and some areas remained. ×: Almost no printed area was removed, or more area than necessary was removed

[0112] [C-3. Embossing Suitability: Shape] The condition after brushing was visually inspected and evaluated according to the following criteria. 〇: The lines indicated by the recesses in the printed area were clearly expressed as drawn. ×: The lines indicated by the recesses in the printed area were not as drawn, and were either flattened or spread out more than drawn.

[0113] [C-4. Embossing Suitability: Workability] After every 10 prints, the condition of the brush after brushing was visually inspected and evaluated according to the following criteria. ◎: No or little peeling residue adhered even after 50 prints, so no cleaning was required ○: Peeling components were found after 50 prints, and cleaning was required. △: After 30 prints, peeling components were found to be attached and cleaning was required. ×: After 10 prints, a large amount of peeling components was found to have adhered, and cleaning was required.

[0114] [C-5. Discharge stability] 〇: There was no disturbance in the print and the ink was discharged stably. △: There was some printing disturbance, but the ink was discharged almost stably. ×: There was printing disturbance or the ink was not ejected stably.

[0115] [Table 2]

[0116] [Table 3]

[0117] As shown in Examples 1 to 9 in Table 2, the ultraviolet ray blocking ink compositions containing predetermined amounts of a photopolymerizable monomer, a non-polymerizable monomer, and an ultraviolet ray absorber each exhibited good ejection stability in inkjet printing, and the evaluation of the substrates having embossed surfaces obtained using the ink compositions was satisfactory or better in all cases.

[0118] In contrast, Comparative Example 1 in Table 3 had a low total content of components with a Tg of 60°C or higher of 2.5% by mass and a high content of UV absorber of 6.0% by mass, and Comparative Example 2 in Table 3 had a high content of UV absorber of 6.0% by mass, and in both examples, workability was poor in the manufacturing process of a substrate having an embossed surface. As described above, it was found that when the content of UV absorber in the UV blocking ink composition is too high, workability deteriorates. This is thought to be because, in the irradiation step, when the area where the UV blocking ink composition is applied is semi-cured, curing does not proceed sufficiently, and a semi-cured product that is only slightly cured and highly sticky adheres to the brush, thereby deteriorating workability.

[0119] In Comparative Example 3 in Table 3, the content of the ultraviolet absorber was as low as 0.3 mass%, and sufficient peeling was not achieved on a substrate having an embossed surface, resulting in a poor evaluation of releasability. This is thought to be because if the content of the ultraviolet absorber in the ultraviolet ray blocking ink composition is too low, curing proceeds excessively when semi-curing the area where the ultraviolet ray blocking ink composition is applied in the irradiation step, causing the hardness of the semi-cured product to increase excessively, making peeling difficult.

[0120] In Comparative Example 4 in Table 3, the content of the non-polymerizable material was low at 4.0 mass%, and workability was poor in the manufacturing process of a substrate having an embossed surface. As described above, it was found that workability deteriorates when the content of the non-polymerizable material in the ultraviolet ray blocking ink composition is too low; this is thought to be because, in the irradiation step, the semi-cured product obtained by semi-curing the area where the ultraviolet ray blocking ink composition was applied had high fastness but was not sufficiently brittle, and the peeled components adhered to the brush, thereby worsening workability.

[0121] Comparative Example 5 in Table 3 did not contain a component with a Tg of 60°C or higher as a non-polymerizable material, and the workability in the manufacturing process of a substrate having an embossed surface was poor. As described above, when the glass transition temperature of the non-polymerizable material in the ultraviolet ray blocking ink composition is low, the semi-cured product obtained by semi-curing the area where the ultraviolet ray blocking ink composition is applied becomes highly tacky in the irradiation step, and this is thought to have adhered to the brush, thereby worsening the workability.

[0122] In Comparative Example 6 in Table 3, the content of the non-polymerizable material was as high as 22.0% by mass, and the viscosity of the ink composition was relatively high, resulting in poor ejection stability.

[0123] Comparative Example 7 in Table 3 had a low total content of components with a Tg of 60°C or higher of 15.0% by mass, which resulted in poor workability in the manufacturing process of a substrate with an embossed surface. This is thought to be because when the total content of components with a Tg of 60°C or higher is too low, the semi-cured product obtained by semi-curing the area where the ultraviolet ray blocking ink composition was applied becomes highly tacky in the irradiation process, and this sticks to the brush, thereby worsening workability.

[0124] Examples 1 to 9 in Table 2 achieved satisfactory results in all evaluations. In both Examples 1 and 2, the component contained in the non-polymerizable material with a Tg of 60°C or higher was DEGALAN LP 66 / 02N, which has a Tg of 70°C, a relatively low Tg. In Example 6, the component contained in the non-polymerizable material with a Tg of 60°C or higher was DEGALAN LP 66 / 02N, which has a Tg of 70°C, and the component contained in the photopolymerizable monomer with a Tg of 60°C or higher was tripropylene glycol diacrylate, which has a Tg of 62°C, both of which are relatively low Tg components.

[0125] On the other hand, in all of Examples 3 to 5, the component contained in the non-polymerizable material and having a Tg of 60°C or higher is Dianale BR-83, which has a Tg of 105°C, and the component contained in the photopolymerizable monomer and having a Tg of 60°C or higher is dipropylene glycol, which has a Tg of 102°C, or acryloylmorpholine, which has a Tg of 145°C, both of which are components with relatively high Tgs. Examples 3 to 5 have improved workability compared to Examples 1 and 2 and Example 6, and it is thought that a higher Tg of the component contained in the non-polymerizable material or photopolymerizable monomer and having a Tg of 60°C or higher is more likely to contribute to improved workability.

[0126] In Example 7, both the photopolymerizable monomer and the non-polymerizable material were composed of components with a Tg of 60° C. or higher, and all evaluation results were good.

[0127] In Example 8, the ratio of monofunctional monomer to polyfunctional monomer used as photopolymerizable monomers was 1:1, and the proportion of polyfunctional monomer in the photopolymerizable monomer was lower than in the other Examples. In Example 8, the workability in the manufacturing process of the substrate having an embossed surface was slightly reduced; this is thought to be because in the irradiation step, the semi-cured product obtained by semi-curing the area where the ultraviolet ray blocking ink composition was applied did not cure sufficiently, and some of the insufficient cured component adhered to the brush, resulting in poor workability.

[0128] In Example 9, the content of the polyfunctional monomer relative to the total amount of the photopolymerizable monomer was approximately 35% by mass, which was set lower than in the other Examples, and all evaluation results were satisfactory. However, the adhesiveness of the semi-cured product obtained by semi-curing the area where the ultraviolet ray blocking ink composition was applied increased slightly, and workability deteriorated slightly. [Industrial Applicability]

[0129] The ink composition for UV protection of the present invention can be printed on any article to suppress UV exposure to the article. In particular, the ink composition for UV protection of the present invention can be suitably used to create an embossed pattern on the surface of an article, and the workability in creating the embossed pattern is excellent. The article having an embossed pattern can also be used as a decorative board for any building material (flooring, wall material, flooring material, etc.), baseboard, furniture, etc. [Explanation of symbols]

[0130] 1 Base material 2-1 Coating film 2-2 Completely cured coating film 2-3 Semi-cured coating film 3-1 UV-shielding ink composition 3-2 Cured product of UV-shielding ink composition 4 Exposure machine 5 Brushes 6 Optional coating layers

Claims

1. 1. An ultraviolet light blocking ink composition for inkjet printing, comprising: the ink composition contains 65.0% by mass or more of a photopolymerizable monomer, 5.0% by mass or more and less than 20.0% by mass of a non-polymerizable material, and 0.5% by mass or more and less than 3.0% by mass of an ultraviolet absorber; The photopolymerizable monomer and the non-polymerizable material contain a photopolymerizable monomer having a glass transition temperature of 60° C. or higher and a non-polymerizable material having a glass transition temperature of 60° C. or higher, respectively; and The ink composition for blocking ultraviolet light, wherein the total content of the photopolymerizable monomer having a glass transition temperature of 60° C. or higher and the non-polymerizable compound is 20 mass % or more relative to the ink composition for blocking ultraviolet light.

2. The ultraviolet ray blocking ink composition according to claim 1 , wherein the content of the polyfunctional monomer in the photopolymerizable monomer is 50.0% by mass or more relative to the photopolymerizable monomer.

3. The ultraviolet ray blocking ink composition according to claim 1 or 2, wherein the photopolymerizable monomer having a glass transition temperature of 60°C or higher comprises a photopolymerizable monomer having a glass transition temperature of 80°C or higher.

4. The ultraviolet ray blocking ink composition according to claim 1 or 2, which is used for inkjet printing on an uncured coating film containing a photopolymerizable compound.

5. A step A of ink jet printing the ultraviolet ray blocking ink composition according to claim 1 onto an uncured coating film containing a photopolymerizable compound that is coated on a substrate; a step B of irradiating the coating film printed with the ultraviolet ray blocking ink composition with ultraviolet rays; and step C of removing the coating film from the area printed with the ultraviolet ray blocking ink composition. A method for producing a substrate having an embossed surface.

6. The method according to claim 5 , wherein the coating film further contains a photopolymerization initiator.

7. The method according to claim 5 or 6, wherein the coating film has a thickness of 30 μm or more.

8. The manufacturing method according to claim 5 or 6, wherein the step C is a mechanical removal step.

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