Manufacturing method of printed matter

Abstract

The present invention provides a method for producing a printed matter, a printed matter, and an electron beam-curable printing ink composition, which are capable of satisfying both the flowability, storage stability, and curing properties of the ink, as well as odor suppression, abrasion resistance, tape adhesion, and lamination suitability of the printed matter. [Solution] The present invention provides a method for producing a printed matter, a printed matter, and an electron beam-curable printing ink composition, the method comprising: a printing step of printing on a printing object using an electron beam-curable printing ink composition containing (A) a polymer of an allyl monomer represented by the following general formula (1), (B) a (meth)acrylate resin, (C) a polyfunctional (meth)acrylate, and (D) a pigment; and a curing step of irradiating the printed electron beam-curable printing ink composition with an electron beam to cure it under conditions of an acceleration voltage of 50 to 150 kV, an exposure dose of 15 to 50 kGy, and an oxygen concentration of 300 ppm or less. JPEG0007669569000013.jpg27161 (In the formula, R 1 and R 2 is H or an alkyl group, and X is a group having an alicyclic skeleton.

Description

[Technical field]

[0001] The present invention relates to a method for producing a printed matter, a printed matter, and an electron beam-curable printing ink composition. [Background technology]

[0002] In active energy ray curable inks, diallyl phthalate resin (sometimes called "DAP resin" or "DAP resin") is used as one of the resin components. Diallyl phthalate resin itself is generally said to be harmless, but its raw material, diallyl phthalate, is a type of phthalate ester and is therefore a chemical substance that raises concerns about its effects on the human body and the environment. For this reason, in recent years, polymers of diallyl cyclohexanedicarboxylate, which are structurally similar, have been considered as alternative materials to diallyl phthalate resin.

[0003] Patent Document 1 discloses an active energy ray-curable ink composition comprising a component (A) which is a polymer of a compound having an ethylenically unsaturated bond and an allyl monomer having a specific structure, and a component (B) which is a rosin-modified resin and / or a terpene monomer skeleton-containing resin.

[0004] Patent Document 2 discloses an active energy ray-curable ink composition that contains (A) a pigment, (B) an allyl resin, (C) an epoxy compound, (D) an oxetane compound, and (E) a photocationic polymerization initiator, and is characterized by the following (1) to (3): (1) The ink composition contains 3 to 25% by weight of (B) an allyl resin. (2) The ink composition contains 30 to 65% by weight of the epoxy compound (C) and the oxetane compound (D) in total. (3) The weight ratio of the (C) epoxy compound / (D) oxetane compound is in the range of 1 to 5. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2023-121316 A [Patent Document 2] JP 2023-161230 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the conventional techniques including Patent Documents 1 and 2, the reality is that there is room for further improvement in terms of achieving both the fluidity, storage stability, and curing properties of the ink, as well as the required properties of suppressing odor of the printed matter, abrasion resistance, tape adhesion, and lamination suitability.

[0007] The present invention has been made in consideration of the above-mentioned circumstances, and has an object to provide a method for producing a printed matter, a printed matter, and an electron beam-curable printing ink composition that can achieve a balance between ink fluidity, storage stability, and curability, as well as odor suppression, abrasion resistance, tape adhesion, and lamination suitability of the printed matter. [Means for solving the problem]

[0008] Means for Solving the Problems The present inventors have conducted intensive research in order to achieve the above-mentioned object, and as a result have discovered an electron beam-curable printing ink composition containing (A) a polymer of an allyl monomer having a specific structure, (B) a (meth)acrylate resin, (C) a polyfunctional (meth)acrylate, and (D) a pigment, thereby completing the present invention.

[0009] That is, the present invention is as follows. <1> The method for producing a printed matter includes: a printing step of printing an object to be printed using an electron beam-curable printing ink composition containing (A) a polymer of an allyl monomer represented by the following general formula (1), (B) a (meth)acrylate resin, (C) a polyfunctional (meth)acrylate, and (D) a pigment; and a curing step of irradiating the printed electron beam-curable printing ink composition with an electron beam to cure it under conditions of an acceleration voltage of 50 to 150 kV, an exposure dose of 15 to 50 kGy, and an oxygen concentration of 300 ppm or less.

[0010] [ka]

[0011] (In the general formula (1), R 1 and R 2 each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, X represents an n-valent group having a 4- to 8-membered alicyclic skeleton, and n is 2 or 3. <2> The (B) component is at least one selected from the group consisting of an epoxy (meth)acrylate resin, a polyester (meth)acrylate resin, and a urethane (meth)acrylate resin. <1> A method for producing a printed matter according to the present invention. <3> The content of the component (A) in the electron beam curable printing ink composition is 3 to 30 mass %. <1> or <2> A method for producing a printed matter according to the present invention. <4> The content of the component (B) in the electron beam curable printing ink composition is 5 to 60 mass %. <1> or <2> A method for producing a printed matter according to the present invention. <5> The content of the component (C) in the electron beam curable printing ink composition is 5 to 60 mass %. <1> or <2> A method for producing a printed matter according to the present invention. <6> The electron beam curable printing ink composition does not contain a polymerization initiator. <1> or <2> A method for producing a printed matter according to the present invention. <7> The electron beam curable printing ink composition is an offset printing ink composition. <1> or <2> A method for producing a printed matter according to the present invention. <8> The electron beam curable printing ink composition is a surface printing ink composition. <1> or <2> A method for producing a printed matter according to the present invention. <9> The electron beam curable printing ink composition is a reverse printing ink composition. <1> or <2> A method for producing a printed matter according to the present invention. <10> <1> or <2> A printed matter is obtained by the method for producing a printed matter described above. <11> The electron beam-curable printing ink composition contains (A) a polymer of an allyl monomer represented by the following general formula (1), (B) a (meth)acrylate resin, (C) a polyfunctional (meth)acrylate, and (D) a pigment, and is cured under the following curing conditions: an acceleration voltage of 50 to 150 kV, an exposure dose of 15 to 50 kGy, and an oxygen concentration of 300 ppm or less. [ka] (In the general formula (1), R 1 and R 2 each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, X represents an n-valent group having a 4- to 8-membered alicyclic skeleton, and n is 2 or 3. Effect of the Invention

[0012] According to the present invention, it is possible to provide a method for producing a printed matter, a printed matter, and an electron beam-curable printing ink composition that can achieve a balance between the fluidity, storage stability, and curing properties of the ink, as well as odor suppression, abrasion resistance, tape adhesion, and lamination suitability of the printed matter. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment for carrying out the present invention (hereinafter, simply referred to as "the present embodiment") will be described in detail. The present embodiment is an example for explaining the present invention, and is not intended to limit the present invention to the following content. The present invention can be carried out by appropriately modifying it within the scope of its gist.

[0014] In addition, in this specification, unless otherwise specified, "(meth)acrylate" includes acrylate and methacrylate. For example, (meth)acrylate means acrylate, methacrylate, or both. The same applies to other similar terms such as "(meth)acrylic".

[0015] <Manufacturing method of printed matter>

[0016] The method for producing a printed matter according to the present embodiment includes a printing step of printing an object to be printed using an electron beam curable printing ink composition containing (A) a polymer of an allyl monomer represented by the following general formula (1), (B) a (meth)acrylate resin, (C) a polyfunctional (meth)acrylate, and (D) a pigment, and a curing step of irradiating the printed electron beam curable printing ink composition with an electron beam to cure the composition under conditions of an acceleration voltage of 50 to 150 kV, an exposure dose of 15 to 50 kGy, and an oxygen concentration of 300 ppm or less. According to this production method, at least the fluidity, storage stability, and curability of the ink, as well as odor suppression, abrasion resistance, tape adhesion, and lamination suitability of the printed matter can be achieved simultaneously. Each component and condition will be described below.

[0017] [ka]

[0018] (In the general formula (1), R 1 and R 2 each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, X represents an n-valent group having a 4- to 8-membered alicyclic skeleton, and n is 2 or 3.

[0019] <Electron beam curable printing ink composition>

[0020] The electron beam curable printing ink composition (hereinafter, sometimes simply referred to as the "ink composition") used in the method for producing a printed matter according to this embodiment is an electron beam curable printing ink composition containing (A) a polymer of an allyl monomer represented by the above general formula (1), (B) a (meth)acrylate resin, (C) a polyfunctional (meth)acrylate, and (D) a pigment.

[0021] The electron beam curable printing ink composition has the ability to be cured by irradiation with active energy rays such as ultraviolet rays and electron beams. As described later, the electron beam curable printing ink composition contains a compound (e.g., a monomer or an oligomer) having an ethylenically unsaturated bond, and is cured by radicals generated in the ink composition when irradiated with active energy rays, which polymerize the compound having an ethylenically unsaturated bond. Therefore, when an ink composition that is sticky on the surface of a printed matter immediately after printing is irradiated with active energy rays, the ink composition instantly cures to become a coating and becomes dry (tack-free). From this perspective, the electron beam curable printing ink composition can sufficiently obtain the desired effect even if it does not contain a polymerization initiator such as a photopolymerization initiator (however, the action and effect of the present embodiment are not limited to these).

[0022] The electron beam curable printing ink composition contains the above-mentioned components (A), (B), (C), and (D), and therefore at least the ink has excellent fluidity, storage stability, and curability, and the printed matter using the same has excellent odor suppression, abrasion resistance, tape adhesion, and lamination suitability. Thus, the electron beam curable printing ink composition has at least the above-mentioned advantages regardless of the printing method, and is suitable as an ink composition for offset printing (for example, an offset printing ink composition, an electron beam curable offset printing ink composition, etc.) because the ink has excellent water compatibility and concentration stability. Details of these will be described later.

[0023] <(A) Polymer of Allyl Monomer>

[0024] The electron beam curable printing ink composition contains component (A), which is a polymer of an allyl monomer represented by the following general formula (1): This polymer is obtained by polymerizing the allyl monomer represented by the following general formula (1) by means of radical polymerization or the like, and the completely polymerized product may be used as an inert resin, which is a binder, or the product in which the polymerization reaction is stopped at about 50% to 80% to leave unreacted unsaturated bonds may be used as a curable component.

[0025] [ka]

[0026] In the general formula (1), R 1 and R 2 are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. In this specification, "each independently" means that each is determined independently without regard to the other, and may be the same as or different from each other. Examples of such alkyl groups include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and a pentyl group. In a preferred embodiment, R 1 and R 2 are each a hydrogen atom, but are not particularly limited thereto.

[0027] In the general formula (1), n ​​is 2 or 3, and X is an n-valent group having an alicyclic skeleton of 4 to 8 members. The term "n-valent group having an alicyclic skeleton of 4 to 8 members" means an n-valent group formed by bonds to other groups from n carbon atoms among the carbon atoms constituting an alicyclic ring having 4 to 8 carbon atoms. X may have an alicyclic skeleton and may also contain other skeletons, but is preferably made of an alicyclic skeleton. In addition, the alicyclic ring of X is preferably a cycloalkane or cycloalkene having 4 to 8 carbon atoms. X may be intramolecularly crosslinked, and examples of intramolecularly crosslinked X include adamantane, norbornene, and norbornane.

[0028] In a more specific embodiment, X is preferably a divalent group represented by any of the following general formulas: In this case, n in general formula (1) is 2.

[0029] [ka]

[0030] Among the Xs represented by the above general formula, a 1,2-cyclohexalene group is preferred. In this case, the 1- and 2-positions of cyclohexane are substituted with the groups represented in parentheses in general formula (1).

[0031] Suitable examples of the allyl monomer represented by general formula (1) include 1,2-cyclohexanedicarboxylate diallyl, 1,3-cyclohexanedicarboxylate diallyl, 1,4-cyclohexanedicarboxylate diallyl, 4-cyclohexene-1,2-dicarboxylate diallyl, 2-cyclohexene-1,2-dicarboxylate diallyl, etc. Among these, 1,2-cyclohexanedicarboxylate diallyl, 4-cyclohexene-1,2-dicarboxylate diallyl, and 1,4-cyclohexanedicarboxylate diallyl are more preferred, and 1,2-cyclohexanedicarboxylate diallyl is even more preferred.

[0032] The allylic monomer represented by the general formula (1) is a cycloalkane or cycloalkene having 4 to 8 carbon atoms and having two or three carboxy groups, and a substituent R 1 and R 2 The compound is obtained by dehydration condensation with an allyl alcohol having the substituent R 1 and R 2 As already described, it is preferable that both of are hydrogen atoms.

[0033] In addition, to obtain a polymer by polymerizing the allyl monomer represented by the general formula (1), the allyl monomer may be polymerized with a radical polymerization initiator. Examples of such radical polymerization initiators include azo initiators such as azobisisobutyronitrile and 2,2'-azobisisobutyrate dimethyl, peroxide initiators such as ketone peroxide, peroxyketal, hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxydicarbonate, peroxyester, and benzoyl peroxide, acetophenone initiators such as 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one and 1-hydroxycyclohexylphenyl ketone, benzoin initiators such as benzoin and benzoin ethyl ether, benzophenone initiators such as benzophenone, phosphorus initiators such as acylphosphine oxide, sulfur initiators such as thioxanthone, and benzyl initiators such as benzyl and 9,10-phenanthrenequinone. The radical polymerization initiator may be used alone or in combination of two or more kinds.

[0034] The amount of the radical polymerization initiator is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and even more preferably 0.001 to 3 parts by mass, relative to 100 parts by mass of the allyl monomer represented by the general formula (1). The reaction temperature during polymerization is not particularly limited, but is usually about 60 to 240° C. The reaction time is about 0.1 to 100 hours.

[0035] In addition, when the allyl monomer represented by the general formula (1) is polymerized to obtain a polymer, a homopolymer using a single allyl monomer may be used, or a copolymer using a combination of multiple allyl monomers and other monomers may be used. In addition, in the copolymer, the other monomers copolymerizable with the allyl monomer are not particularly limited, but examples thereof include 3-methyl-hexahydro-1,2-diallyl phthalate, 4-methyl-hexahydro-1,2-diallyl phthalate, 3-methyl-1,2,3,6-tetrahydro-1,2-diallyl phthalate, and 4-methyl-1,2,3,6-tetrahydro-1,2-diallyl phthalate. A preferred embodiment of the present invention is a homopolymer of 1,2-cyclohexanedicarboxylate diallyl, but is not particularly limited thereto.

[0036] The weight average molecular weight of the polymer is not particularly limited, but is preferably 2,000 to 300,000. The lower limit is more preferably 5,000 or more, and even more preferably 10,000 or more. The upper limit is more preferably 200,000 or less, even more preferably 150,000 or less, and even more preferably 140,000 or less. Unless otherwise specified, the weight average molecular weight is the polystyrene-equivalent weight average molecular weight (M) obtained by gel permeation chromatography (GPC) analysis. w )

[0037] As such a polymer, a polymer synthesized as described above or a commercially available product, for example, a product manufactured by Osaka Soda Co., Ltd., may be used.

[0038] The component (A) may use one type alone, or two or more types in combination.

[0039] The content of component (A) in the entire electron beam curable printing ink composition is not particularly limited, but is preferably 3 to 30 mass%. The lower limit is more preferably 5 mass% or more, and even more preferably 10 mass% or more. The upper limit is more preferably 25 mass% or less, and even more preferably 15 mass% or less. When the electron beam curable printing ink composition of this embodiment contains a solvent, the above content is preferably the content when the entire solid content is 100 mass%.

[0040] <(B) (Meth)acrylate Resin>

[0041] The electron beam curable printing ink composition contains a (meth)acrylate resin. Examples of the (meth)acrylate resin include resins having a (meth)acrylate skeleton having one or more functional groups selected from the group consisting of an epoxy group, an ester group, an ether group, and a urethane group. Specific examples thereof include epoxy (meth)acrylate resins, polyester (meth)acrylate resins, urethane (meth)acrylate resins, and polyether (meth)acrylate resins.

[0042] Among these, it is preferable that component (B) is at least one selected from the group consisting of epoxy (meth)acrylate resins, polyester (meth)acrylate resins, and urethane (meth)acrylate resins, which can further improve the adhesion of the ink coating film and the lamination suitability of the printed matter.

[0043] The epoxy (meth)acrylate resin may be, for example, an aromatic (meth)acrylate resin having a bisphenol skeleton or the like, or an aliphatic (meth)acrylate resin having a hydrogenated bisphenol skeleton or the like. Commercially available products may be used.

[0044] The polyester (meth)acrylate resin may be, for example, an aliphatic polyester (meth)acrylate, an aromatic polyester (meth)acrylate, etc. Commercially available products may also be used.

[0045] Examples of the urethane (meth)acrylate resin that can be used include polyester urethane (meth)acrylate, polyether urethane (meth)acrylate, polycarbonate urethane (meth)acrylate, etc. Commercially available products may also be used.

[0046] The component (B) may be used alone or in combination of two or more types.

[0047] The content of component (B) in the entire electron beam curable printing ink composition is not particularly limited, but is preferably 5 to 60 mass%. The lower limit is more preferably 10 mass% or more, and even more preferably 15 mass% or more. The upper limit is more preferably 50 mass% or less, and even more preferably 40 mass% or less. When the electron beam curable printing ink composition of this embodiment contains a solvent, the above content is preferably the content when the entire solid content is 100 mass%.

[0048] <(C) Polyfunctional (meth)acrylate>

[0049] The electron beam curable printing ink composition contains (C) a polyfunctional (meth)acrylate. The polyfunctional (meth)acrylate compound can enhance the curability of the ink composition by electron beam. Note that the term "polyfunctional" refers to the number of (meth)acrylate groups contained in one molecule, and is preferably bifunctional to hexafunctional.

[0050] Specific examples of the component (C) include, but are not limited to, dihydric alcohol di(meth)acrylates such as 1,4-butanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 2-methyl-1,8-octanediol di(meth)acrylate, 2-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, and tripropylene glycol di(meth)acrylate; polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, and tris(2-hydroxyethyl)isocyanate. di(meth)acrylate of annulate, di(meth)acrylate of diol obtained by adding 4 moles or more of ethylene oxide or propylene oxide to 1 mole of neopentyl glycol, di(meth)acrylate of diol obtained by adding 2 moles of ethylene oxide or propylene oxide to 1 mole of bisphenol A; poly(meth)acrylate of trihydric or higher polyhydric alcohol such as trimethylolpropane tri(meth)acrylate, glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, poly(meth)acrylate of dipentaerythritol; tri(meth)acrylate of triol obtained by adding 3 moles or more of ethylene oxide or propylene oxide to 1 mole of glycerin, trimethylolpropane tri(meth)acrylate of 3 moles or more of ethylene oxide or propylene oxide to 1 mole of trimethylolpropane, Examples of such poly(meth)acrylates include di- or tri(meth)acrylates of triols obtained by adding 1 mole of bisphenol A to 1 mole of ethylene oxide or propylene oxide, and poly(meth)acrylates of polyoxyalkylene polyols such as di(meth)acrylates of diols obtained by adding 4 or more moles of ethylene oxide or propylene oxide to 1 mole of bisphenol A; vegetable oil (e.g. soybean oil) modified epoxy acrylates; and urethane acrylates.

[0051] Among these, alkylene oxide-modified trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, alkylene oxide-modified glycerin (meth)acrylate, soybean oil-modified acrylate, urethane acrylate, and the like are preferred; ditrimethylolpropane tetra(meth)acrylate, tri(meth)acrylate of an ethylene oxide 3-mol adduct of trimethylolpropane, tri(meth)acrylate of an ethylene oxide 6-mol adduct of trimethylolpropane, tri(meth)acrylate of a propylene oxide 3-mol adduct of trimethylolpropane, tri(meth)acrylate of a propylene oxide 3-mol adduct of glycerin, dipentaerythritol hexaacrylate, and the like are more preferred.

[0052] The component (C) may use one type alone, or two or more types in combination.

[0053] The (C) component is preferably a compound having a low glass transition temperature (for example, preferably 100°C or less, more preferably 60°C or less). The (C) component having a low glass transition temperature can improve the lamination suitability of the ink composition. Specific examples of (meth)acrylate compounds having a low glass transition temperature include, but are not limited to, di- or tri(meth)acrylates of triols obtained by adding 3 moles or more of ethylene oxide or propylene oxide to 1 mole of trimethylolpropane. In addition, when two or more kinds of (C) components are used in combination, for example, it is preferable that 50 mass% or more of the (C) component is a compound having a low glass transition temperature, and it is more preferable that 60 mass% or more of the (C) component is a compound having a low glass transition temperature.

[0054] The content of component (C) in the entire electron beam curable printing ink composition is not particularly limited, but is preferably 5 to 60 mass%. The lower limit is more preferably 10 mass% or more, and even more preferably 20 mass% or more. The upper limit is more preferably 55 mass% or less, and even more preferably 50 mass% or less. When the electron beam curable printing ink composition of this embodiment contains a solvent, the above content is preferably the content when the entire solid content is 100 mass%.

[0055] <(D) Pigment>

[0056] The electron beam curable printing ink composition includes a pigment (D). The type of the pigment (D) is not particularly limited, but examples thereof include inorganic pigments and organic pigments. Specific examples of inorganic pigments include color pigments such as carbon black, graphite, antimony red, cadmium yellow, cobalt blue, Prussian blue, ultramarine blue, and titanium oxide (including achromatic color pigments such as white and black); and extender pigments such as graphite, zinc, lime carbonate powder, calcium carbonate, gypsum, clay, silica (silicon dioxide), diatomaceous earth, talc, kaolin, alumina white, barium sulfate, aluminum stearate, magnesium carbonate, magnesium silicate, baryte powder, and glass beads. Specific examples of organic pigments include soluble azo pigments, insoluble azo pigments, azo lake pigments, condensed azo pigments, copper phthalocyanine pigments, and condensed polycyclic pigments.

[0057] The component (D) may be used alone or in combination of two or more types.

[0058] The extender pigment can more effectively adjust the rheological properties of the ink composition. The extender pigment is also expected to effectively prevent sticking of printed matter by being localized on the surface (outer surface) of the cured film formed by the ink composition (however, the functions and effects of the present embodiment are not limited to these).

[0059] A suitable example of the extender pigment is one that contains at least (D-1) calcium carbonate, magnesium carbonate, or magnesium silicate in combination with (D-2) silica (silicon dioxide). This combination, together with other components, can more effectively suppress the stringiness (tendency to form strings) of the ink composition. The content ratio (mass ratio) of the (D-1) component to the (D-2) component is not particularly limited, but is preferably 10:1 to 1:1, more preferably 10:1 to 2:1, even more preferably 10:1 to 4:1, and even more preferably 10:1 to 6:1.

[0060] The content of the extender pigment in component (D) relative to the entire electron beam curable printing ink composition is not particularly limited, but is preferably 0.1 to 10 mass%. The lower limit is more preferably 1 mass% or more, and even more preferably 2 mass% or more. The upper limit is more preferably 8 mass% or less, and even more preferably 6 mass% or less. When the electron beam curable printing ink composition of this embodiment contains a solvent, the above content is preferably the content when the entire solid content is taken as 100 mass%.

[0061] <(E) Other ingredients, etc.>

[0062] The electron beam curable printing ink composition may contain any other components other than those described above, so long as the functions and effects of the composition are achieved. Examples of other components include colorants other than component (D), pigment dispersants, waxes, polymerization inhibitors, surfactants, solvents, etc.

[0063] Examples of colorants other than component (D) include dyes, such as dye lakes (basic reaction type lakes, acid dye lakes, etc.), and nitro pigments.

[0064] Examples of the pigment dispersant include polymeric pigment dispersants. The polymeric pigment dispersant is preferably a pigment dispersant containing a basic group. Specific examples of the pigment dispersant containing a basic group include polymeric pigment dispersants such as basic group-containing polyester pigment dispersants, basic group-containing acrylic pigment dispersants, basic group-containing urethane pigment dispersants, and basic group-containing carbodiimide pigment dispersants; anionic surfactants, etc. The polymeric pigment dispersant is not particularly limited, but a linear polymer having a pigment affinity portion consisting of a basic group at least at the end of the main chain (at one end or both ends) due to a block structure or graft structure can be used.

[0065] Examples of waxes include animal and vegetable waxes such as beeswax, lanolin wax, spermaceti, candelilla wax, carnauba wax, rice wax, Japan wax, and jojoba oil; minerals such as montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, and petrolatum; petroleum-based waxes; synthetic hydrocarbon waxes such as Fischer-Tropsch wax, polyethylene wax, oxidized polyethylene wax, and oxidized polypropylene wax; fluororesin waxes such as polytetrafluoroethylene wax; mixtures of polytetrafluoroethylene wax and polyethylene wax; modified waxes such as montan wax derivatives, paraffin wax derivatives, and microcrystalline wax derivatives; hydrogenated waxes such as hydrogenated castor oil and hydrogenated castor oil derivatives; and polytetrafluoroethylene wax.

[0066] The polymerization inhibitor can effectively prevent unintended polymerization reactions from occurring during storage of the ink composition, and can effectively suppress thickening of the ink composition. Examples of the polymerization inhibitor include phenolic compounds (including quinone compounds) such as dibutylhydroxytoluene (BHT), tocopherol acetate, nitrosamine compounds, benzotriazole, hindered amines, and the like. Among these, phenolic compounds such as dibutylhydroxytoluene are preferred. The content of the polymerization inhibitor in the ink composition can be appropriately set depending on the type of polymerization inhibitor, but for example, in the case of phenolic compounds such as dibutylhydroxytoluene (BHT), it can be about 0.3 to 2.0 parts by mass when the entire curable component is 100 parts by mass.

[0067] Examples of the surfactant include a nonionic surfactant, a cationic surfactant, an anionic surfactant, a betaine surfactant, etc. Specific examples of the surfactant include a silicone-based surfactant such as polyether-modified silicone oil, polyester-modified polydimethylsiloxane, polyester-modified methylalkylpolysiloxane, etc., a fluorine-based surfactant, an acetylene-based surfactant, etc.

[0068] The electron beam curable printing ink composition can be cured by irradiation with an electron beam even if it does not contain a polymerization initiator. Therefore, the ink composition may or may not contain a polymerization initiator, but it is preferable that it does not contain one. Specific examples of such polymerization initiators include those other than the above-mentioned components, such as acylphosphine oxide compounds, thioxanthone compounds, aromatic ketones, aromatic onium salt compounds, organic peroxides, thio compounds (such as compounds containing a thiophenyl group), α-aminoalkylphenone compounds, hexaarylbiimidazole compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having a carbon-halogen bond, and alkylamine compounds.

[0069] The electron beam curable printing ink composition may or may not contain a solvent such as water or an organic solvent. For example, the solvent may be a small amount (e.g., 3 mass % or less relative to the mass of the ink composition). Unless otherwise specified, when the electron beam curable printing ink composition in this embodiment contains a solvent, the content value described in this specification is preferably the content when the entire solid content is 100 mass %.

[0070] The viscosity of the electron beam curable printing ink composition is preferably 100.0 Pa·s or less, and more preferably 1.0 Pa·s to 90.0 Pa·s. The viscosity may be measured using a cone plate viscometer at 25°C and a shear rate of 100 / s. When the viscosity is within the above numerical range, the fluidity and transferability of the ink composition are further improved, and the stability of the ink composition supplied to the roller in offset printing is improved, and the printing workability is also expected to be improved. In addition, when the viscosity is within the above numerical range, the leveling property of the ink composition transferred to the printing object (printed substrate, etc.) is further improved, and quality problems such as gloss deterioration are expected to be more effectively suppressed. Furthermore, when the viscosity of the ink composition is within the above numerical range, the tack value as an ink can be easily controlled to a suitable value, and therefore, it is expected that transfer failure to the printing object can be effectively suppressed and stable printing workability can be ensured.

[0071] The electron beam curable printing ink composition has a property (curability) of being cured by irradiation with an electron beam. From this viewpoint, the electron beam curable printing ink composition is preferably an electron beam curable printing ink composition that contains (A) a polymer of an allyl monomer represented by the above general formula (1), (B) a (meth)acrylate resin, (C) a polyfunctional (meth)acrylate, and (D) a pigment, and is used for curing under the curing conditions of an acceleration voltage of 50 to 150 kV, an exposure dose of 15 to 50 kGy, and an oxygen concentration of 300 ppm or less. The degree of curability is not particularly limited, but it is preferable that, for example, when formed into a coating film, it is completely cured with an exposure dose of 20 to 40 kGy.

[0072] <Method for producing electron beam curable printing ink composition>

[0073] The electron beam curable printing ink composition can be obtained by carrying out a step of mixing the above-mentioned components (A) to (D) and, if necessary, other components (component (E) and the like). For example, the composition can be obtained by dissolving the polymer of an allyl monomer (A) or the (meth)acrylate resin (B) in the polyfunctional (meth)acrylate (C), dispersing the pigment (D), and mixing with any other components (component (E) and the like). The mixing means and the like are not particularly limited.

[0074] <Printing process, curing process, printed matter, etc.>

[0075] In the method for producing a printed matter according to the present embodiment, a printing step of printing on a printing target is performed, followed by a curing step of curing the printed electron beam curable printing ink composition by irradiating an electron beam. In the printing step, a suitable method can be appropriately selected depending on the material used and the application, and for example, a method of applying the electron beam curable printing ink composition to the printing target can be adopted. The printing method in the printing step is not particularly limited, and various methods described below can be adopted. In the curing step, an electron beam is irradiated under conditions of an acceleration voltage of 50 to 150 kV, an exposure dose of 15 to 50 kGy, and an oxygen concentration of 300 ppm or less. The material of the printing target (printed object) is not particularly limited as long as the ink composition is electron beam curable on the target, and can be appropriately selected depending on the application, but the acceleration voltage, exposure dose, and oxygen concentration in the above ranges can effectively exhibit the above-mentioned various advantages of the present embodiment.

[0076] The acceleration voltage may be 50 to 150 kV as described above, but the lower limit is preferably 60 kV or more, more preferably 70 kV or more, and even more preferably 80 kV or more, and the upper limit is preferably 140 kV or less, more preferably 130 kV or less, and even more preferably 110 kV or less.

[0077] The irradiation dose may be 15 to 50 kGy as described above, but the lower limit is preferably 20 kGy or more, and the upper limit is preferably 40 kGy or less.

[0078] As described above, the oxygen concentration may be 300 ppm or less, but the upper limit is preferably 250 ppm or less, more preferably 200 ppm or less, and even more preferably 150 ppm or less, and the lower limit is preferably 50 ppm or more, more preferably 70 ppm or more, and even more preferably 80 ppm or less.

[0079] The method for producing a printed matter according to the present embodiment is also excellent in water compatibility and concentration stability, and therefore can be suitably used for offset printing. From such a viewpoint, the method for producing a printed matter according to the present embodiment is preferably offset printing. For example, a production method including a step of offset printing an electron beam curable printing ink composition onto a printing target (offset printing step) and a step of irradiating the offset-printed electron beam curable printing ink composition with an electron beam to cure it (curing step) is exemplified. Below, the printing method according to the present embodiment will be described by way of example, taking offset printing as an example, but it goes without saying that it is not limited to the following aspect.

[0080] The printing target in the offset printing process is not particularly limited, and examples of the printing target substrate include a resin substrate, a metal substrate, a paper substrate, etc. Specific examples of the metal of the metal substrate include aluminum, zinc, copper, iron, tin, etc. Specific examples of the paper substrate include synthetic paper, art paper, coated paper, cast paper, sawn paper, resin laminated paper, metal vapor deposition paper, metal oxide vapor deposition paper, etc.

[0081] Considering the effects and advantages of the present embodiment, such as improved adhesion to the printing object and lamination suitability, a resin substrate, particularly a resin film, may be preferable. The type of resin constituting the resin substrate is not particularly limited, but examples include films or sheets of polyester resin (e.g., polyethylene terephthalate), acrylic resin, vinyl chloride resin, vinylidene chloride resin, polyvinyl alcohol, polyethylene, polypropylene, polyacrylonitrile, ethylene vinyl acetate copolymer, ethylene vinyl alcohol copolymer, ethylene methacrylic acid copolymer, nylon, polylactic acid, polycarbonate, cellophane, aluminum foil, and various other resins that have been used as printing objects (printing substrates) in the past. The resin film may be subjected to a stretching process (uniaxial stretching, biaxial stretching, etc.).

[0082] The offset printing process may be carried out in accordance with a method for a known printing process, and may, for example, include a method including the steps of: (a) supplying the electron beam curable printing ink composition according to this embodiment and dampening water to a plate; (b) transferring the ink composition supplied to the plate to a blanket (off-step); and (c) fixing the ink composition transferred to the blanket to the printing target (set step).

[0083] The dampening solution supplied to the plate is a solution mainly composed of water, and may contain optional components such as pH adjusters, water-soluble organic solvents, chelating compounds, water-soluble polymers, etc.

[0084] In step a of supplying the ink composition and dampening water to the plate, for example, the ink composition can be supplied to the plate wound around the plate cylinder by an ink roller, and the dampening water can be supplied to the plate by a water fountain roller. A plate usually has a portion to which the ink composition is attached (lipophilic image portion) and a portion to which the dampening water is attached (hydrophilic non-image portion). The ink composition is attached to the image portion of the plate, and the attached ink composition may be an emulsion of the ink composition and dampening water (water-in-oil emulsion).

[0085] The ink composition (or an emulsion with dampening water) adhering to the image area of ​​the plate is transferred to the blanket (step b). The dampening water adhering to the non-image area of ​​the plate is collected without being transferred to the blanket cylinder. Furthermore, the ink composition (or an emulsion with dampening water) transferred to the blanket is usually pressed against the printing object (printed substrate, etc.) by an impression cylinder and fixed on the printing object to form a coating (step c).

[0086] The coating film formed on the printing target by offset printing is cured by irradiation with an electron beam to form a cured film, and is fixed as an image. In the case of offset printing, the accelerating voltage of the electron beam is preferably in the range of 80 to 150 kV, more preferably in the range of 80 to 110 kV, from the viewpoint of suitably suppressing the penetration of the electron beam into the printing target and suppressing damage to the printing target. In addition, the irradiation dose of the electron beam to be irradiated is preferably in the range of 20 to 40 kGy, from the viewpoint of reliably curing the coating film and suppressing poor adhesion to the substrate due to excessive curing. In addition, from the viewpoint of effectively preventing damage to the printing target (printing substrate, etc.) due to a high irradiation dose or a high accelerating voltage, it is preferable to appropriately set the upper limit of these parameters.

[0087] According to this embodiment, a printed matter can be obtained by performing printing by the above-mentioned method. The various conditions of the printing process can be appropriately selected from the various conditions described above. The printed matter obtained by the manufacturing method according to this embodiment is excellent in odor suppression, abrasion resistance, tape adhesion, lamination suitability, etc. as a printed matter.

[0088] <Applications of ink compositions and printed matter>

[0089] The method for producing a printed matter according to the present embodiment is printed on a printing object and cured to form a printed layer, thereby giving a printed matter. The method for producing a printed matter according to the present embodiment may be used to produce a printed matter by reverse printing (reverse printing ink composition), may be used to produce a printed matter by front printing (front printing ink composition), or may be used for other printing forms. In the case of front printing, for example, a production method including a step of front printing an electron beam curable printing ink composition on a printing object (front printing printing step) and a step of irradiating the front-printed electron beam curable printing ink composition with an electron beam to cure it (curing step) can be mentioned. In addition, in the case of reverse printing, for example, a production method including a step of back printing an electron beam curable printing ink composition on a printing object (reverse printing printing step) and a step of irradiating the back-printed electron beam curable printing ink composition with an electron beam to cure it (curing step) can be mentioned.

[0090] In the case of surface printing (surface printing ink composition), the printed layer is exposed on the surface of the printed matter, and therefore high adhesion between the printed substrate and the printed layer is required. In this regard, the electron beam curable printing ink composition according to the present embodiment is excellent at least in adhesion, and therefore the printed layer (printed part) obtained from the ink composition has high adhesion to the printed substrate and can be suitably used in surface printing.

[0091] In the case of reverse printing (when the ink composition is used for reverse printing), a laminate is generally obtained by laminating a laminate layer covering a printed layer. Therefore, the printed matter obtained by reverse printing is required to have high lamination suitability (the laminate layer is not easily peeled off). In this regard, the method for producing a printed matter according to the present embodiment is excellent in at least lamination suitability, and therefore the printed layer obtained from the ink composition can be strongly adhered to the laminate layer via an adhesive or the like, and therefore can be suitably used in reverse printing.

[0092] In other words, a cured product of the electron beam curable printing ink composition according to this embodiment is fixed to a base film, which is the substrate to be printed, to form an image, an adhesive is applied so as to cover the cured product to form an adhesive layer, and a sealant layer is further laminated on the adhesive layer to obtain a laminate film (a laminate film comprising, in this order, a base film, which is the substrate to be printed, a cured product layer of the ink composition, an adhesive layer, and a sealant layer).

[0093] The substrate film, which is the substrate to be printed, is preferably made of a resin, but is not particularly limited and can be selected according to the application of the resulting laminate film. The adhesive layer is a cured product of an adhesive composition, but the composition of the adhesive composition is not particularly limited. The sealant layer arranged so as to cover the adhesive layer is preferably made of a resin, for example, polyolefin, but can be selected according to the application of the laminate film.

[0094] The sealant layer may be formed by any of the following methods: dry lamination, solventless lamination, and extrusion lamination. In order to effectively exhibit the effects of the electron beam curable printing ink composition according to this embodiment (high adhesion to the substrate to be printed and high lamination suitability), it may be preferable to form the sealant layer by the dry lamination method.

[0095] The laminate film thus obtained has the advantage that it is easy to ensure sufficient lamination suitability because of the high adhesion between the printed substrate and the cured layer of the ink composition, and also between the cured layer of the ink composition and the adhesive layer. The laminate film thus obtained is used for any purpose, for example, for a wide range of lamination purposes such as food packaging and food preservation packaging.

[0096] As described above, the method for producing a printed matter, the printed matter, and the electron beam curable printing ink composition according to the present embodiment can achieve both the fluidity, storage stability, and curability of the ink, as well as the odor suppression, abrasion resistance, tape adhesion, and lamination suitability of the printed matter. Such advantages are expected to be exhibited in a wide range of printing methods. In addition, since the ink has excellent water compatibility and concentration stability, it can be suitably used for offset printing, which allows clear printing to be easily and mass-produced in a short time.

[0097] The method for producing a printed matter, the printed matter, and the electron beam curable printing ink composition according to the present embodiment can be suitably used for both front printing and rear printing. For example, in the case of package printing, in the case of front printing, printing is performed on the front side of the package (bag), and the electron beam curable printing ink composition according to the present embodiment is expected to effectively suppress problems such as the ink rubbing off.

[0098] In the case of reverse printing, printing is performed from the reverse side of a transparent material such as a bag, and the printed layer is covered with a laminate layer. The printed layer is visible to the user from the front side through the transparent material. In this respect, the electron beam curable printing ink composition according to the present embodiment has excellent lamination suitability, so that even if the contents are food or other items that require safety, the lamination effect is sufficiently maintained, and the ink components do not contaminate the contents, and the contents can be expected to be stored safely and hygienically for a long period of time.

[0099] As described above, the method for producing a printed matter, the printed matter, and the electron beam curable printing ink composition according to the present embodiment can be suitably used in a wide range of printing methods, but the advantages of the method are particularly evident in offset printing. The method is also suitable for printing on food packages and food preservation packages. The food referred to here is not limited to the shape or content of the food, and solid, semi-solid, fluid, and liquid foods can be preserved. EXAMPLES

[0100] The present invention will be described in more detail below with reference to examples, but the scope of the present invention is not limited to these examples. The amounts of the components shown in each table are in parts by mass.

[0101] <Preparation of Electron Beam-Curable Printing Ink Composition>

[0102] First, the materials used to prepare the electron beam curable printing ink compositions of the Examples and Comparative Examples are shown below.

[0103] (resin) AD-032: Homopolymer of 1,2-cyclohexanedicarboxylate diallyl (see formula (i) below) (product name "RADPAR-AD032", manufactured by Osaka Soda Co., Ltd., non-phthalate allyl resin)

[0104] [ka]

[0105] A-DAP: homopolymer of diallyl phthalate (product name "Daiso DAP A", manufactured by Osaka Soda Co., Ltd.) VS-1063: Polystyrene (product name "VS-1063", polystyrene, weight average molecular weight (M w )5,500, manufactured by Seiko PMC) ISODAP: homopolymer of diallyl isophthalate (product name "Daiso Isodap", manufactured by Osaka Soda Co., Ltd.)

[0106] (Polymerizable compound (polyfunctional)) M410: Ditrimethylolpropane tetraacrylate (product name "MIRAMER M410", manufactured by Miwon) M3130: Triacrylate of 3 moles of ethylene oxide adduct of trimethylolpropane (product name "MIRAMER M3130", manufactured by Miwon) M3160: Triacrylate of 6 moles of ethylene oxide adduct of trimethylolpropane (product name "MIRAMER M3160", manufactured by Miwon) M360: Triacrylate of 3 moles of propylene oxide adduct of trimethylolpropane (product name "MIRAMER M360", manufactured by Miwon) M320: Triacrylate of 3 moles of propylene oxide adduct of glycerin (product name "MIRAMER M320", manufactured by Miwon) M600: Dipentaerythritol hexaacrylate (product name "MIRAMER M600", manufactured by Miwon)

[0107] (Polymerizable compound (monofunctional)) IBXA: Isobornyl acrylate (product name "IBXA", manufactured by Osaka Organic Chemical Industry Co., Ltd.)

[0108] ((Meth)acrylate resin) PE210: Bisphenol A skeleton-containing epoxy diacrylate (product name "MIRAMER PE210", manufactured by Miwon) 623-100: Bisphenol A-containing epoxy acrylate (product name "ETERCURE 623-100", manufactured by Eternsl Materials) EBECRYL600: Aromatic epoxy acrylate (product name "EBECRYL600", manufactured by Daicel-Allnex Corporation) EBECRYL3700: Aromatic epoxy acrylate (product name "EBECRYL3700", manufactured by Daicel-Allnex Corporation) EBECRYL3702: Fatty acid modified epoxy acrylate (product name "EBECRYL3702", manufactured by Daicel Allnex Co., Ltd.) PE310: Soybean oil modified epoxy acrylate (product name "MIRAMER PE310", manufactured by Miwon) EBECRYL438: A mixture of 60 parts by mass of chlorinated polyester acrylate and 40 parts by mass of glycerin propoxy triacrylate (product name "EBECRYL438", manufactured by Daicel-Allnex Corporation) DR-U161: Aliphatic urethane acrylate (product name "ETERCURE DR-U161", manufactured by Eternsl Materials)

[0109] (Extender pigment) T-DD: Calcium carbonate (product name "Hakuenka T-DD", manufactured by Shiraishi Calcium Co., Ltd.) L-1: Talc (product name "L-1", manufactured by Nippon Talc Co., Ltd.) CP-102: Silica (product name "Reoloseal CP102", manufactured by Tokuyama Corporation)

[0110] (Other pigments) MA-70: Carbon black (product name "MA-70", manufactured by Mitsubishi Chemical Corporation)

[0111] (Pigment dispersant) Solsperse 33000: Basic functional group-containing copolymer (amine value 43.0 mgKOH / g, acid value 27 mgKOH / g, active ingredient 100% by mass, manufactured by Lubrizol Japan)

[0112] (wax) MG: Synthetic wax (product name "S-394 MG", manufactured by Shamrock Technologies)

[0113] (Polymerization inhibitor) BHT: Dibutyl hydroxytoluene

[0114] (film) OPP: Stretched polypropylene film (product name "P2161", manufactured by Toyobo Co., Ltd.) PE: Uniaxially oriented polyethylene film (manufactured by JINDAL) OPA: Stretched nylon film (product name "Emblem ONM-15", manufactured by Unitika Ltd.) PET: Polyethylene terephthalate film (product name "E-5102", manufactured by Toyobo Co., Ltd.)

[0115] The components were blended to obtain the composition shown in each table (% by mass unless otherwise specified), and the blended components were kneaded using a three-roll mill to obtain an electron beam curable printing ink composition (ink composition) for each Example and Comparative Example.

[0116] <Evaluation method>

[0117] The electron beam curable printing ink compositions (ink compositions) and printed matter of each of the Examples and Comparative Examples were evaluated in the following manner.

[0118] (Liquidity assessment) For the ink compositions of each Example and Comparative Example, the flow value was measured using a spread meter, and the fluidity was evaluated as the flow slope value. The flow slope value is a value obtained by subtracting the value of the spread diameter measured in mm after 10 seconds from the value of the spread diameter measured in mm after 100 seconds using the spread meter, and the larger this value, the better the fluidity was evaluated to be. 5: The flow slope value was 10 or more. 4: The flow slope value was 5 or more and less than 10. 3: The flow slope value was 3 or more and less than 5. 2: The flow slope value was 1 or more and less than 3. 1: The flow slope value was less than 1.

[0119] (Evaluation of storage stability) The viscosity of the ink compositions of each Example and Comparative Example 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 20 rpm. The ink compositions were then stored at 25°C for 30 days in a stationary state, and the viscosity at 25°C was then measured again in the same manner as before storage. The storage stability was evaluated by calculating the rate of change in viscosity before and after storage using the following formula. Viscosity change rate (%) = ((viscosity after storage - viscosity before storage) / viscosity before storage) x 100 5: The absolute value of the viscosity change rate was 3% or less. 3: The absolute value of the viscosity change rate was more than 3% and 5% or less. 1: The absolute value of the viscosity change rate exceeded 5%.

[0120] (Evaluation of curability) 0.1 mL of the ink composition of each Example and Comparative Example was spread on an OPP film using an RI spreader (two-split roll, manufactured by Akebono Seisakusho Co., Ltd.). Then, electron beam irradiation (EB irradiation device, irradiation conditions are conditions shown in the "EB curing conditions" column in Tables 1 to 4) was repeated until the ink coating film printed on the printed matter was cured, and the number of irradiations (passes) was counted until the ink was cured. The state in which the ink did not adhere when the coating film was rubbed with a cotton swab was judged to be cured. Cured in 5:1 pass. Cured in 4:2 passes. Cured in 3:3 passes. Cured in 2:4 passes. It cured in 1:5 passes or more, or it did not cure at all.

[0121] (Evaluation of water width suitability) First, unless otherwise noted, printing was performed on printing paper using the following procedures and conditions to produce printed matter. Printing machine: Komori Corporation, 4-color, single-sided, 100-size format Print speed: 12,000sph Printing plate: Fujifilm Global Graphic Systems, XP-F (CTP plate) AM175 line Printing paper: Nippon Paper Industries, OK Coat L

[0122] Printing was started with the dampening water feed dial value of the printing press at 30, and when 10,000 sheets had been printed, the dampening water feed dial value was lowered to 15 (reducing the amount of dampening water supplied). The ink stain concentration (OD value) in the plain areas (non-image areas) of the prints obtained when the dial value was lowered was measured, and the water width suitability was evaluated according to the following criteria. 5: The ink stain density of the plain area was less than 0.01. 4: The ink stain concentration on the plain area was 0.01 or more and less than 0.05. 3: The ink stain concentration on the plain area was 0.05 or more and less than 0.1. 2: The ink stain concentration on the plain area was 0.1 or more and less than 0.2. 1: The ink stain concentration on the plain area was 0.2 or more.

[0123] (Evaluation of concentration stability) Using the ink compositions of each Example and Comparative Example, prints were produced under the same conditions as in "(Evaluation of Water Width Suitability)" above. However, the amount of dampening water supplied was changed by 10% increments between 10 and 60% (increasing the amount of dampening water supplied), and the print density (OD value) of the image part of the prints obtained at each amount of dampening water supplied was measured. The amount of dampening water supplied represents the number of rotations (%) of the water source roller. Then, using a spectrodensitometer / colorimeter "eXact Advance" manufactured by X-Rite, the decrease rate of print density (OD value) was calculated according to the following formula.

[0124]

number

[0125] 5: The concentration reduction rate was 0%. 4: The concentration decrease rate was greater than 0% and less than 5%. 3: The concentration decrease rate was more than 5% and less than 10%. 2: The concentration decrease rate was more than 10% and 15% or less. 1: The concentration decrease rate exceeded 15%.

[0126] (Odor evaluation) 0.1 mL of the ink composition of each Example and Comparative Example was applied to an OPP film using an RI color application machine (two-split roll, manufactured by Mei Seisakusho Co., Ltd.). Then, electron beam irradiation was performed until the ink coating film printed on the printed matter was cured, to obtain a printed matter. The conditions of electron beam irradiation were an acceleration voltage of 90 kV, an exposure dose of 30 kGy, and an oxygen concentration of 100 ppm, except for the curability evaluation of Comparative Examples 14 to 16. In Comparative Examples 14 to 16, the curing evaluation was also performed under the conditions described in the "EB curing conditions" in the table. Then, the presence or absence of odor was confirmed by four panelists for the printed matter using such an OPP film as a substrate. 5: No one noticed any odor. 4: 1 person noticed an odor. 3: 2 people noticed an odor. 2:3 people noticed an odor. 1: All participants noticed the odor.

[0127] (Evaluation of abrasion resistance) The above-mentioned printed matter using the OPP film as a substrate was rubbed 200 times with a 500g weight via a pressing cloth (Kanakin No. 3), and the condition of the coating after this rubbing was visually observed. 5: No scratches were observed on the surface of the cured film. 4: Scratches were observed on the surface of the cured film, but no peeling was observed. 3: Less than half of the entire surface of the cured film was peeled off, and less than half of the base was visible. 2: More than half of the entire surface of the cured film had peeled off, revealing more than half of the base. 1: The entire cured film peeled off.

[0128] (Preparation of cured products using films other than OPP as substrate) 0.1 mL of the ink composition of each Example and Comparative Example was applied to each film (PE, OPA, PET) other than OPP using an RI color application machine (two-split roll, manufactured by Akebono Seisakusho Co., Ltd.). Then, electron beam irradiation was performed until the ink coating film printed on the printed matter was cured, to obtain a printed matter. The conditions of electron beam irradiation were an acceleration voltage of 90 kV, an exposure dose of 30 kGy, and an oxygen concentration of 100 ppm, except for the curability evaluation of Comparative Examples 14 to 16. In Comparative Examples 14 to 16, the curing evaluation was also performed under the conditions described in the "EB curing conditions" in the table.

[0129] (Tape adhesion) Cellophane tape (manufactured by Nichiban Co., Ltd., product name "Cellotape (registered trademark)") was applied to the cured coating surface of the print using each of the above films (OPP, PE, OPA, PET) as a substrate, and then peeled off in one go. The peeled area of ​​the cured coating was evaluated on a 5-point scale according to the following criteria. The smaller the peeled area, the better the adhesion between the cured coating and the resin film was evaluated to be. 5: No peeling at all. 4: The area of ​​the peeled hardened coating was greater than 0% and less than 20%. 3: The area of ​​the peeled hardened coating was more than 20% but not more than 50%. 2: The area of ​​the peeled hardened coating was more than 50% but not more than 75%. 1: The peeled off hardened coating covered more than 75% of the surface area.

[0130] (Lamination suitability) First, an adhesive (Mitsui Chemicals, "Takelac A969V / Takenate A-5") was applied at a solid content of 3.5 g / m2 onto the cured coating surface of the print using each of the above films (OPP, PE, OPA, PET) as the substrate. 2 The coating was applied in an amount of 0.01g / g and a non-oriented polypropylene film ("GLC", 40μm thick, manufactured by RM Tocello Co., Ltd.) was laminated using a dry laminator. The tensile strength of each laminate was measured using a tensile tester (manufactured by Yasuda Seiki Seisakusho Co., Ltd.) at a measurement temperature of 25°C and a tensile speed of 200mm / min. The lamination suitability was evaluated based on the following criteria. 5: The peel strength was 1.5 N / 15 mm or more. 4: The peel strength was 1.0 N / 15 mm or more and less than 1.5 N / 15 mm. 3: The peel strength was 0.5 N / 15 mm or more and less than 1.0 N / 15 mm. 2: The peel strength was 0.1 N / 15 mm or more and less than 0.5 N / 15 mm. 1: The peel strength was less than 0.1 N / 15 mm.

[0131] Tables 1 to 4 show the compositions and evaluation results of the ink compositions of the respective Examples and Comparative Examples.

[0132] [Table 1]

[0133] [Table 2]

[0134] [Table 3]

[0135] [Table 4]

[0136] From the above, it was confirmed that the method for producing printed matter of this embodiment at least provides excellent ink fluidity, storage stability, curing property, water resistance, and concentration stability, and also provides printed matter with excellent odor suppression, abrasion resistance, tape adhesion, and lamination suitability.

Claims

1. A printing process in which an electron beam curable printing ink composition containing (A) a polymer of an allyl monomer represented by the following general formula (1), (B) a (meth)acrylate resin, (C) a polyfunctional (meth)acrylate, and (D) a pigment is used to print on a printing object by offset printing; a curing step of irradiating the printed electron beam-curable printing ink composition with an electron beam under conditions of an acceleration voltage of 50 to 150 kV, an exposure dose of 15 to 50 kGy, and an oxygen concentration of 50 to 300 ppm to cure the composition, The electron beam curable printing ink composition is an offset printing ink composition, The electron beam curable printing ink composition does not contain a polymerization initiator, the component (B) is at least one selected from the group consisting of an epoxy (meth)acrylate resin, a polyester (meth)acrylate resin, and a urethane (meth)acrylate resin, The component (C) is at least one selected from the group consisting of ditrimethylolpropane tetra(meth)acrylate, a tri(meth)acrylate of an adduct of trimethylolpropane with 3 or more moles of ethylene oxide, a tri(meth)acrylate of an adduct of trimethylolpropane with 3 or more moles of propylene oxide, a tri(meth)acrylate of an adduct of glycerin with 3 or more moles of propylene oxide, and dipentaerythritol hexaacrylate. A method for producing printed matter. 【Chemistry 1】 (In the general formula (1), R １ and R ２ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, X represents an n-valent group having a 4- to 8-membered alicyclic skeleton, and n is 2 or 3.

2. the component (C) is at least one selected from the group consisting of ditrimethylolpropane tetra(meth)acrylate, a tri(meth)acrylate of an ethylene oxide 3-mol adduct of trimethylolpropane, a tri(meth)acrylate of an ethylene oxide 6-mol adduct of trimethylolpropane, a tri(meth)acrylate of a propylene oxide 3-mol adduct of trimethylolpropane, a tri(meth)acrylate of a propylene oxide 3-mol adduct of glycerin, and dipentaerythritol hexaacrylate; A method for producing the printed matter according to claim 1 .

3. The content of the component (A) in the electron beam curable printing ink composition is 3 to 30 mass %. A method for producing the printed matter according to claim 1 or 2.

4. The content of the component (B) in the electron beam curable printing ink composition is 5 to 60 mass %. A method for producing the printed matter according to claim 1 or 2.

5. The content of the component (C) in the electron beam curable printing ink composition is 5 to 60 mass %. A method for producing the printed matter according to claim 1 or 2.

6. The electron beam curable printing ink composition is a surface printing ink composition. A method for producing the printed matter according to claim 1 or 2.

7. The electron beam curable printing ink composition is a reverse printing ink composition. A method for producing the printed matter according to claim 1 or 2.

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