WO2017199902A1

WO2017199902A1 - Active energy ray-curable reverse offset printing ink

Info

Publication number: WO2017199902A1
Application number: PCT/JP2017/018164
Authority: WO
Inventors: 正義高武; 森田　進; 朋子岡本
Original assignee: Dic株式会社
Priority date: 2016-05-16
Filing date: 2017-05-15
Publication date: 2017-11-23
Also published as: TW201811940A

Abstract

This active energy ray-curable reverse offset printing ink contains a volatile solvent and an active energy ray-curable resin having active energy ray-polymerizable groups and is characterized in that the surface tension of the ink at 25°C is 15-27 mN/m. The content of extender pigment having a volume-average particle size of 1-150 nm is preferably in the 20-300 mass% range relative to 100 mass% of the total active energy ray-curable resin in the active energy ray-curable reverse offset printing ink.

Description

Active energy ray curable reversal offset printing ink

The present invention relates to an active energy ray-curable ink for reverse offset printing that is used for reverse offset printing, is active energy ray-curable, and can form an insulating film.

Conventionally, laser ablation and photoresist etching have been used to form a fine insulating layer used in various electronic devices.
In recent years, a technique for forming an insulating layer by printing has been studied. For example, a printed electronic device typified by a TFT is required to form a conductive pattern and an insulating layer by printing using nano Ag ink. There is.
Patent Document 1 describes an active energy ray-curable ink for an insulating film of an organic thin film transistor. Patent Document 2 describes an ink composition for forming an insulating film of an organic transistor.

JP 2014-3068 A International Publication No. 2009/150972

The reverse offset printing is the only printing method that can form a fine pattern comparable to the photolithographic method. Introduction of reverse offset printing has been demanded as a method for printing conductive patterns of various electronic devices typified by printing TFTs and printing methods for metal grids applied to touch panels and the like. Further, if the ink used for the reverse offset printing is active energy ray curable, it is possible to cure the fine pattern printed at a low temperature in a short time. If the cured film of the ink after energy beam curing has an insulating property, the cured film can be used as an insulating layer.
However, conventionally, there has been no report that an ink that can be used for reversal offset printing, is energy beam curable, and has a cured film having an insulating property after curing.
Although Patent Document 1 describes an active energy ray-curable ink for an insulating film, there is no specific description that can be applied to reverse offset printing.
Although Patent Document 2 describes an ink composition for forming an insulating film of an organic transistor, the ink composition is thermosetting and not active energy ray curable. The heat treatment of the thermosetting ink requires a certain amount of processing time, which is a great limitation on productivity and construction of a low-cost process for practical use. Moreover, since a certain amount of heating is required, there is a limit to application to a substrate having poor heat resistance such as PET.

That is, an object of the present invention is to provide an active energy ray-curable ink for reverse offset printing, which can be used for reverse offset printing, is active energy ray-curable, and has a cured film cured by irradiation with active energy rays. It is to provide.

The present invention adopts the following configuration as means for solving the above-described problems.
(1) containing an volatile solvent and an active energy ray-curable resin having an active energy ray-polymerizable group, and having an ink surface tension of 15 to 27 mN / m at 25 ° C. Energy beam curable reversal offset printing ink.
(2) An active pigment with a volume average particle diameter of 1 to 150 nm is contained in a range of 20 to 300% by mass with respect to 100% by mass of the total active energy beam curable resin in the ink for active energy beam curable reversal offset printing. The active energy ray-curable reversal offset printing ink according to (1).
(3) Active energy ray curable 10 to 80 mass of active energy ray curable resin having a weight average molecular weight (Mw) of 6000 to 40,000 with respect to 100 mass% of all active energy ray curable resins in the ink for reverse offset printing. % Active energy ray-curable reversal offset printing ink according to the above (1) or (2).
(4) The cured film cured by active energy ray irradiation has a water contact angle of greater than 95 ° and a contact angle of n-hexadecane of greater than 50 °, as described in any one of (1) to (3) above Active energy ray curable reversal offset printing ink.
(5) The active energy ray-curable reverse offset printing ink contains 1 to 80% by mass of the energy ray-polymerizable fluorine-based surfactant with respect to 100% by mass of the total active energy ray-curable resin. The active energy ray-curable reversal offset printing ink according to any one of (4).

According to the present invention, there is provided an energy ray-curable ink for reverse offset printing that can be used for reverse offset printing, is active energy ray-curable, and has a cured film cured by irradiation with active energy rays. Can do.

It is a schematic diagram explaining an example of the procedure of the reverse offset printing method.

Hereinafter, embodiments of the present invention will be described.
As one embodiment of the present invention, it contains a volatile solvent and an active energy ray-curable resin having an active energy ray-polymerizable group, and the surface tension of the ink at 25 ° C. is 15 to 27 mN / m. An active energy ray-curable reversal offset printing ink is provided. The energy beam curable reverse offset printing insulating ink preferably contains a surfactant.

<Reverse offset printing>
FIG. 1 is a schematic diagram for explaining an example of the procedure of the reverse offset printing method. Reverse offset printing has the following steps.
(Process 1: Inking process)
First, apply the reverse offset printing ink to the blanket 2 and dry it appropriately.
An ink coating film 1 is formed on the blanket. The blanket may be in the form of a roll or a plate, but here a roll is shown.
(Process 2: Off process / Pattern process)
Next, the printing plate (letter plate) 3 having a concavo-convex pattern is pressed against the ink coating film 1, the ink coating film in contact with the protruding portion of the printing plate is removed from the blanket, and a pattern is formed on the ink coating film 1 on the blanket 2. . The punching plate may be in the form of a roll or a plate, but here a plate is shown.
(Process 3: Set process)
Thereafter, the ink coating film 1 patterned on the blanket 2 is transferred to the substrate 4.

Here, as the material of the blanket 2, silicone rubber (PDMS) having an appropriate solvent absorbability and excellent in ink pattern formation / transferability can be suitably used. Examples of the material of the punch plate 3 include glass, metal, and resin.

There are no restrictions on the material of the substrate 4, various plastic films such as polyester film, polycarbonate film and polyimide film, various printed wiring substrates such as phenolic substrates, paper epoxy substrates, glass epoxy substrates and alumina substrates, and various metals such as stainless steel. Foil, various plastic substrates, various papers, various glass such as general blue plate glass, quartz, sapphire, and silicone substrates can be applied according to the purpose.

Unlike other printing methods such as gravure printing and flexographic printing, the reverse offset printing method performs pattern formation and the printing process in a state where there is no ink fluidity, so there is no sagging of ink, and image quality is improved. An excellent fine pattern can be formed. The ink applicable to the reverse offset printing method is required to be suitable for the process. In the inking process, for example, it is required that a uniform ink thin film can be formed on silicone rubber having high liquid repellency without repelling or uneven printing thickness. Further, in the patterning process, for example, it is required that the pattern of only the convex portion of the punching plate that comes into contact is removed from the thin film on the blanket, and the necessary pattern remains on the blanket. Furthermore, in the setting process, for example, it is required that the pattern on the blanket is completely transferred onto the substrate without remaining.
The inventors of the present invention have found that a reversal offset printing ink satisfying these requirements can be formed by using a specific energy ray-curable tree composition that forms an insulating cured film, and have led to the present invention.

≪Ink for active energy ray curable reversal offset printing≫
Hereinafter, the active energy ray-curable reverse offset printing ink of the present invention may be referred to as “reverse offset print ink” or “ink”. Further, a cured film obtained by curing the ink for reverse offset printing by irradiation with active energy rays may be referred to as “cured film of ink for reverse offset printing” or “cured film”.

Since reverse offset printing usually includes the steps as described above, it is preferable that the reverse offset printing ink has the following ink characteristics so that each step can be performed.
In Step 1, the ink for reverse offset printing has excellent “wetting” with respect to the blanket so that a uniform ink coating film can be formed on the silicone rubber blanket with high liquid repellency without repellency or uneven printing thickness. Is preferred.
In step 2, the ink film of the reverse offset printing ink has excellent “cutting properties” and excellent “transferability to the cutting plate” so that the pattern can be accurately removed only on the convex portions of the printing plate that comes into contact. "Is preferably exhibited. The cutting property affects the “pattern forming property” of whether or not a fine pattern can be formed.
In step 3, the ink film of the reverse offset printing ink has excellent transferability to the substrate so that the ink film patterned on the blanket is transferred to the substrate without any ink transfer remaining on the blanket. Is preferable.

<Ink composition>
The ink for reverse offset printing according to the embodiment contains a volatile solvent and an active energy ray-curable resin as one component. In addition, the reverse offset printing ink of the present embodiment preferably contains a substance having characteristics as a surface energy adjusting agent such as a surfactant in order to realize an optimum surface tension.

(solvent)
The solvent contained in the ink for reversed offset printing of the embodiment may be an organic solvent, and any solvent system can be used as long as it dissolves the active energy ray-curable resin. For example, various types of aliphatic hydrocarbon solvents, various aromatic hydrocarbon solvents, ester solvents, ketone solvents, various alkylene glycol solvents, various ether solvents, various amide solvents, etc. Two or more types may be included.

Ink characteristics suitable for various ink coating methods on the blanket can be realized by containing an appropriate solvent in the ink. As an ink coating method for the blanket, a capillary coating method, a slit die coating method, a dip coating method, a screen printing method, an ink jet method, and the like can be suitably applied. For example, when a slit die coating method or a capillary coating method is applied, the ink viscosity is preferably 1 to 100 mPa · s, more preferably 1.5 to 50 mPa · s, and further preferably 3 to 20 mPa · s.

The ink for reversal offset printing of the embodiment preferably has a storage elastic modulus of 1 × 10 ³ Pa to 1 × 10 ⁷ Pa of a semi-dried coating film formed on a blanket and having a solvent appropriately dissipated, It is more preferably 1 × 10 ⁴ Pa to 1 × 10 ⁶ Pa, and further preferably 1 × 10 ⁴ Pa to 5 × 10 ⁵ Pa. In addition, the reverse offset printing ink of the embodiment is formed on the blanket, and the complex viscosity of the semi-dried coating film in which the solvent is appropriately dissipated is 1 × 10 ² Pa · s to 1 × 10 ⁶ Pa · s. It is preferably 5 × 10 ² Pa · s to 5 × 10 ⁵ Pa · s, more preferably 1 × 10 ³ Pa · s to 1 × 10 ⁵ Pa · s.
The ink has a solvent dissipation when applied onto the blanket. Therefore, in this specification, the “semi-dry state” can be said to be a state of a coating film formed on a blanket in reverse offset printing.
The viscoelasticity value of the semi-dry film reproduces the amount of solvent remaining in the ink coating film in Step 2 of the reverse offset printing, and uses a rotary rheometer Gemini manufactured by Malvern Co. The measured value is measured at a measurement frequency of 1 Hz using a gap of 30 μm at a temperature of 25 ° C. and a strain of 1%.

The volatile solvent contained in the ink for reversed offset printing of the embodiment may be an organic solvent, and any solvent can be used as long as it dissolves the active energy ray-curable resin. This ink contains a volatile solvent. In the present specification, the “volatile solvent” refers to a solvent having a boiling point measured at atmospheric pressure of 60 ° C. to 200 ° C., preferably 60 ° C. to 180 ° C. Atmospheric pressure refers to 1013.25 hPa. The volatile solvent may be a volatile organic solvent. By containing a volatile solvent, ink characteristics required for reverse offset printing can be expressed at an industrial production level.

By using a volatile solvent as a component of the ink, the dissipation of the solvent from the ink coating formed on the blanket proceeds rapidly, and the ink coating is semi-finished in a drying time of several tens of seconds to several minutes after coating. It can be made into a dry state, and appropriate tackiness and cohesiveness can be expressed in the coating film, and pattern formation and transferability can be expressed in Step 2 and Step 3.

Examples of volatile organic solvents that can be suitably used include aliphatic hydrocarbon volatile organic solvents such as hexane, heptane, octane, decane, isohexane, isooctane, cyclohexane, methylcyclohexane, toluene, o-xylene, m- Aromatic hydrocarbon volatile solvents such as xylene, p-xylene, ethylbenzene, mesitylene, dichlorobenzene, chloronaphthalene, diethylbenzene, ethyl acetate, isopropyl acetate, n-propyl acetate, isobutyl acetate, n-butyl acetate, methyl propionate Ester volatile solvents such as ethyl propionate, alcohol volatile solvents such as methanol, ethanol, propanol, isopropanol, sec-butanol, tert-butanol, cyclohexanol, α-terpineol, acetone, methyl ethyl Ketone volatile solvents such as ketone, methyl isobutyl ketone, cyclohexanone, 2-hexanone, 2-heptanone, 2-octanone, diethylene glycol ethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl Alkylene glycol volatile solvents such as ether, propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, diethylene glycol methyl ether acetate, dipropyl ether, diisopropyl ether, dibutyl ether, butyl vinyl ether, anisole, methoxytoluene, benzyl ethyl ether, dioxane, Ethers such as tetrahydrofuran There are amide type volatile solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, etc., but there is no particular limitation. These may be used alone or in combination of two or more.

The amount of the solvent in the active energy ray-curable reversal offset printing ink of the embodiment is preferably 30% by mass or more, more preferably 70% by mass or more, and further preferably 80% by mass or more in 100% by mass of the total ink. The amount of the solvent in the active energy ray-curable reversal offset printing ink of the embodiment is preferably 30 to 98% by mass, more preferably 70 to 95% by mass, and more preferably 80 to 90% by mass, based on 100% by mass of the total ink. preferable. Further, the proportion of the volatile solvent in the embodiment in the total solvent can be appropriately adjusted according to the ink coating method and the environment, and may be contained in 60 to 100% by mass in 100% by mass of the total solvent.

The ink coating film of the ink containing the solvent in the above range forms a coating film excellent in cutting property, patterning property and transferability on the blanket, and in the above step 2, from the ink coating film on the blanket. The pattern can be accurately removed.

The energy ray curable reversal offset printing ink of the embodiment has a surface tension of 15 to 27 mN / m, preferably 16 to 24 mN / m, more preferably 17 to 22 mN / m. The surface tension of the ink can be determined by the method described in the examples.
When the surface tension of the ink is within the range, a uniform ink coating film can be formed on the surface of the liquid repellent blanket in the step 1 (inking step). The surface tension of the ink may be adjusted by selecting the solvent type to be used or adding a surfactant. As the surfactant, various surface energy adjusting agents such as a silicone-based surfactant and / or a fluorine-based surfactant can be suitably applied. In particular, the fluorine-based surfactant has a large ink surface tension adjusting ability, and an expected effect can be obtained by adding a small amount. Further, these fluorine-based surfactants can improve the pattern forming property and transfer property of the ink coating film in the

above steps

2 and 3 as well as improving the liquid repellency of the ink cured film and the film quality such as surface smoothness. It is more preferable.
Among these, nonionic fluorosurfactants can be preferably applied as an insulating film to various electronic devices without fear of adverse effects due to ions.

Specific examples of the fluorosurfactant include, for example, Megafuck F-444, Megafuck F-251, Megafuck F554, Megafuck F-555, Megafuck F-558, Megafuck F-559, Megafuck F-560, Megafuck F-561, Megafuck F-562, Megafuck F-563, Megafuck F-568, Megafuck F-569, Megafuck F-570 (all from DIC Corporation) PF-636, PF-6320, PF-656, PF-6520, PF-652-NF (all of which are manufactured by Kitamura Chemical Sangyo), Surflon S-611, Surflon S-651 (all of which are above) AGC SE A chemical product or the like can be suitably used.
Among these fluorosurfactants, those of the oligomer type are preferably applicable because they exhibit effects in improving the ink patterning property and transferability in addition to the ink surface energy adjustment function.
The surfactant may be added in an amount of 0.001 to 4% by mass, 100 to 2% by mass, or 0.1 to 1% by mass per 100% by mass of the ink for reverse offset printing. % May be blended.

(Active energy ray curable resin)
In the present specification, the active energy ray-curable resin may be a polymer, monomer, or oligomer having an active energy ray polymerizable group (functional group) in the molecule. The active energy ray curable resin may contain a structural unit derived from an active energy ray curable monomer having an active energy ray polymerizable group in the molecule. One or more active energy ray-curable monomers can be used.

Examples of the active energy ray functional group include (meth) acryloyl group, oxetane group, epoxy group, thiol group, maleimide group, as well as various alkylene groups such as methylene and ethylene, isocyanate group, hydroxyl group, alkoxysilyl group and the like. It is done.

Examples of the active energy ray-curable resin having a bifunctional or higher functional (meth) acryloyl group as a functional group include various acrylic monomers, various urethane acrylates, various polyester acrylates, various polybutadiene acrylates, various silicone acrylates, various amino acids. Resin acrylates, (meth) acryloyl group-substituted various silsesquioxane compounds having a composite structure of organic and inorganic, and oligomers or polymers obtained by polymerizing these basic skeletons can be applied. Examples of bifunctional or higher acrylic monomers include ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, tetramethylene ether glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, and trimethylolpropane. Or (meth) acrylate containing three polymerizable double bonds having no cyclic structure such as tri (meth) acrylate of the alkylene oxide adduct, tetra (meth) acrylate of pentaerythritol or its alkylene oxide adduct, etc. Polymerizable double bonds having no cyclic structure such as (meth) acrylate, dipentaerythritol or hexa (meth) acrylate of an alkylene oxide adduct thereof containing four polymerizable double bonds having no cyclic structure 6 pieces (Meth) acrylate, tris (2-hydroxylethyl), triallyl isocyanurate, ethoxylated isocyanuric acid acrylates such as acrylic acid esters, adducts of isophorone diisocyanate and hydroxyethyl (meth) acrylate A polyfunctional (meth) acrylate having two or more polymerizable double bonds in a molecule such as (meth) acrylate having two or more polymerizable double bonds having a cyclic structure can be used.

Further, hydroxy acrylates such as hydroxyethyl acrylate and hydroxypropyl acrylate, alkyl acrylates such as isobutyl acrylate, n-octyl acrylate and t-butyl acrylate, isobornyl acrylate, tetrahydrofurfuryl acrylate, cyclohexyl acrylate, Phenoxyethyl acrylate, ethyl carbitol acrylate, methoxypolyethylene glycol acrylate, 2-methyl-2-ethyl-1,3-dioxolan-4-yl) methyl acrylate, (3-ethyloxetane-3-yl) methyl acrylate, cyclic tri Single officers such as methylolpropane formal acrylate, cyclopentynyl acrylate and other alicyclic / aromatic / ether acrylates, amadantyl acrylates, etc. Acrylate may appropriately applied.

Examples of active energy ray-curable resins having a thiol group as a functional group include trimethylol ethane tris (3-mercaptobutyrate) trimethylolpropane tris (3-mercaptobutyrate), pentaerythritol tetrakis (3-mercaptobutyrate), 1,4 bis (3-mercaptobutyloxy) butane can be preferably used.

Examples of the energy ray curable resin having a maleimide group as a functional group include 4,4′-diphenylmethane bismaleimide, polyphenylmethane maleimide, m-phenylene bismaleimide, bisphenol A diphenyl ether bismaleimide, 4-methyl-1,3. -Phenylene bismaleimide, 1,6-bismaleimide- (2,2,4-trimethyl) hexane, 3,3′-dimethyl-5,5′-diethyl-4,4′-diphenylmethane bismaleimide, maleimide acrylate, etc. Can be used.

Examples of the photocationic energy ray curable resin include 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate and a modified ε-caprolactone, bis- (3,4 epoxycyclohexylmethyl) adipate. An alicyclic epoxy resin such as diepoxy limonene can be suitably applied. Further, 1,4-bis [(3-ethyl-3-octacel) methoxymethyl] benzene, 3-ethyl-3-{[(3-ethyloxetane-3-yl) methoxy] alone or in combination with these resins Oxetane compounds such as methyl} oxetane, vinyl compounds such as diallyl phthalate, divinyl ethylene urea, divinyl adipate, ethylene glycol, trimethylol propane, various polyether polyols, various polyester polyols, various caprolactone polyols, oxetanyl groups in the molecule Various silsesquioxane compounds introduced in can be applied.

Further, not only compounds having a cation-reactive single functional group such as an epoxy group, oxetane group or vinyl group in one molecule, but also compounds having a plurality of types of functional groups in the same molecule are applicable. For example, a compound containing a vinyl ether group and an epoxy group in the same molecule, a reactive compound having a propenyl ether group and an epoxy group, and the like can be applied.

Also, if necessary, a reactive component having a radical crosslinking curing mechanism having a (meth) acryloyl group and a cation crosslinking curing mechanism such as an oxetane group or an epoxy group may be hybridized. Hybridization is performed by, for example, mixing a radical curable component such as an acroyl group-containing compound and a radical curing initiator as necessary with a cationic curable composition containing an epoxy compound, an oxetane compound, a vinyl compound or the like as a reactive compound. Is obtained. Preferred examples of the acroyl group-containing compound include compounds having a cationic polymerizable vinyl ether and a radical polymerizable acroyl group in the same molecule, such as (meth) acrylic acid (vinyloxy) ether.

In 100% by mass of the active energy ray-curable reversal offset printing ink, the active energy ray-curable resin may be contained in an amount of 2 to 70% by mass, or may be contained in an amount of 5 to 50% by mass. It may be contained in an amount of 12% by mass or 12 to 20% by mass.
The content of the active energy ray-curable resin within the above range can be appropriately selected depending on the required cured film thickness, strength, insulation, etc., and the content of the ink containing the active energy ray-curable resin within the above range can be selected. The ink coating film has excellent cutting properties and transferability, and can form a printing pattern with excellent image quality.

The ink for reverse offset printing of the embodiment has a property of curing when irradiated with active energy rays. Here, as the active energy, high active energy rays such as electron rays and X-rays can be used in addition to ultraviolet rays and visible rays. When photocuring using ultraviolet light or visible light, the ink for reverse offset printing may contain a photopolymerization initiator suitable for the functional group of the polymerization system as necessary.

As the photopolymerization initiator, known ones may be used. For example, at least one selected from the group consisting of acetophenones, benzyl ketals, and benzophenones can be preferably used. Examples of the acetophenones include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 4 -(2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone and the like. Examples of the benzyl ketals include 1-hydroxycyclohexyl-phenyl ketone and benzyl dimethyl ketal. Examples of the benzophenones include benzophenone and methyl o-benzoylbenzoate. Examples of the benzoins include benzoin, benzoin methyl ether, and benzoin isopropyl ether. A photoinitiator may be used independently and may use 2 or more types together.

Also, when the active energy ray-curable monomer has a photocationically polymerizable group such as a vinyl ether group or an epoxy group, a photocation initiator can be used in combination. Examples of the photocation initiator include a diazonium salt of a Lewis acid, an iodonium salt of a Lewis acid, a sulfonium salt of a Lewis acid, and the cation part is an aromatic diazonium, an aromatic iodonium, an aromatic sulfonium, and an anion. Preferably, the moiety is an onium salt composed of BF4-, PF6-, SbF6-, [BY4]-(wherein Y is a phenyl group substituted with at least two fluorine atoms or a trifluoromethyl group) or the like. Is a cationic polymerization initiator which is a phosphorus compound from the viewpoint of stability. Specifically, boron difluoride phenyldiazonium salt, phosphorus hexafluoride diphenyliodonium salt, antimony hexafluoride diphenyliodonium salt, arsenic hexafluoride tri-4-methylphenylsulfonium salt, antimony tetrafluoride List tri-4-methylphenylsulfonium salt, diphenyliodonium salt of tetrakis (pentafluorophenyl) boron, acetylacetone aluminum salt and orthonitrobenzylsilyl ether mixture, phenylthiopyridium salt, phosphorus hexafluoride allene-iron complex, etc. Can do.

Commercially available photopolymerization initiators include Irgacure 651, Irgacure 184, Irgacure 819, Irgacure 907, Irgacure 1870, Irgacure 500, Irgacure 369, Irgacure 1173, Irgacure 2959, Irgacure 4265, Irgacure 4263, Darocur OPO 01, Irgac・ Specialty Chemicals Co., Ltd.). Also, cationic photopolymerization of Irgacure 250 (Ciba Specialty Chemicals Co., Ltd.), CPI100P, CPI101A, CPI-200K, CPI210S (San Apro Co., Ltd.), Adekaoptomer SP300, SP150 (Adeka Co., Ltd.), etc. Agents can also be used.

The blending amount of the photopolymerization initiator is preferably 0.1 to 15% by mass and more preferably 1 to 10% by mass with respect to 100% by mass of the active energy ray-curable resin. Preferably, the content is 2 to 5% by mass.

The ink for reversal offset printing according to the embodiment may contain extender pigments as necessary in addition to the solvent and the active energy ray-curable resin having an active energy ray polymerizable group.

The extender pigment may be a known and commonly used color pigment alone or fine particle powder alone, and one or two or more are used. The extender pigment may be an inorganic fine particle powder. These simple color pigments and fine particle powders may be used in the form of a pigment dispersion previously dispersed in a dispersant or an organic solvent. Examples of the fine particle powder include titanium oxide fine particles, zirconia fine particles, alumina fine particles, silica fine particles, carbon particles, hollow silica fine particles, and tantalum oxide fine particles.

Specifically, EXCEDIC BLUE0565, EXCEDIC RED 0759, EXCEDIC YELLOW 0599, EXCEDIC GREEN0358, EXCEDIC YELLOW0648 (product name DIC), Aerosil series (product name Evonik), Silicia, Silo, Silo Pure, Thylosphere, Silo Mask, Silwell, Fuji Balloon (product name: Fuji Silysia), PMA-ST, IPA-ST, PGM-Ac-2140Z (product name: Nissan Chemical), NANOBIC3600 series, NANOBIC3800 series (product name: Big Chemie) ), 12S, 13M, 13MC (trade name: Mitsubishi Materials Electronic Chemicals), etc. There is no. These may be used alone or in combination of two or more.

These extender pigments can be selected in accordance with the industrial application of the ink of the embodiment.
For example, when the ink of the embodiment is applied to various electronic devices as an insulating film, silica particles, alumina particles, zirconia particles, and the like excellent in insulating properties can be suitably applied.
When used as a light shielding film, titanium black or carbon black fine particles can be applied.
In addition, when the reverse offset printing ink according to the embodiment is applied to, for example, a gate insulating film of an organic transistor as an electronic element, the insulating film is required to have high thin film insulating properties and excellent dielectric properties, as well as surface smoothness of a cured film. In these insulating film applications, the volume average particle size of the extender pigment added to the ink is preferably 1 to 150 nm, more preferably 1 to 50 nm, and even more preferably 2 to 30 nm. For these applications, PGM-Ac-2140Z, PMA-ST, IPA-ST (trade name: Nissan Chemical), NANOBIC 3600 series trade name, manufactured by Big Chemie), which are fine particle silica dispersion or alumina dispersion, can be suitably applied. The volume average particle diameter represents the median diameter d50 equivalent. The volume average particle diameter of the extender pigment can be easily measured by, for example, a dynamic light scattering method.

The extender pigment having a volume average particle diameter of 1 to 150 nm may be contained in the range of 20 to 300% by mass with respect to 100% by mass of the total active energy beam curable resin in the ink for active energy beam curable reversal offset printing. Preferably, it is contained in the range of 50 to 200% by mass.
When the content is 20% by mass or less, these effects cannot be obtained effectively, and when the content is more than 300% by mass, the fragility of the ink cured film is increased, which may limit the industrial application field.
By including the specific extender pigment in the ink for reversed offset printing according to the embodiment, the industrial application of the cured film described above can be expanded and the printing characteristics of the ink can be improved. . By adding the extender pigment to the ink, it is possible to improve the pattern forming property by the drawing plate in the reverse offset printing step 2. In particular, it can be made excellent in thick film pattern formability. The type and particle size of the extender pigment contained in the ink can be selected according to the application application of the ink cured film. For example, silica sol having a particle diameter of about 2 to 30 nm can be suitably used for applications where fine pattern formation with a film thickness of several μ and a line width of 5 μm is required and surface smoothness of the cured film is required.

The ink for reversal offset printing according to the embodiment comprises 10 to 80% by mass of the active energy ray curable resin having a weight average molecular weight (Mw) of 6000 to 40,000 with respect to 100% by mass of the total active energy ray curable resin in the ink. It is preferably contained in the range of 20 to 75% by mass, more preferably in the range of 25 to 65% by mass, and more preferably in the range of 30 to 65% by mass. Is particularly preferred.

The weight average molecular weight (Mw) of the active energy ray-curable resin having a weight average molecular weight (Mw) of 6000 to 40,000 may be 6200 to 35000 or 6500 to 30000.

In the ink of the embodiment, the active energy ray curable resin having an Mw of less than 6000 with respect to the total energy ray curable resin amount is less than 90% by mass with respect to 100% by mass of the total active energy ray curable resin in the ink. It is preferable to contain. And it is preferable to contain less than 20 mass% of energy-beam curable resin whose Mw exceeds 40000.

The reverse offset printing method makes use of the transient viscoelastic change of semi-dry ink caused by the time-dependent dissipation of the solvent from the uniform ink film coated on the blanket, realizing fine pattern formation and transfer Printing technology. In order to make the reverse offset printing technique a printing technique that can withstand practical use, it is required to maintain a semi-dry state of ink that can be patterned and transferred in an optimal time (process window) for the process.

As a result of intensive studies, the present inventors can easily design an ink composition having a wider printing process window and excellent printing characteristics by containing an energy ray-curable resin having an Mw of 6000 to 40,000 in a specific amount of ink. I discovered that. In addition, this configuration makes it possible to apply a wide variety of energy ray hardened resins to the design of the reverse offset printing ink, thereby realizing application to various industrial uses. For example, it can be applied to various insulating film applications such as an insulating film used in various electronic devices such as power semiconductors, LED lighting, and inverter devices that require high electrical insulation, and a gate insulating film of a TFT.
In addition, various resist inks can be designed as materials for microlenses that require high optical characteristics. These resist inks for reverse offset printing make it possible to replace resist pattern formation with a printing method which is a simpler process by photolithography in precision pattern plating technology.

The ink according to the embodiment preferably contains an energy ray curable resin having an Mw of less than 6000 in an amount of less than 90% by mass with respect to 100% by mass of the total energy ray curable resin, and more preferably in an amount of 80% by mass or less. preferable. If the ratio of the energy ray curable resin having an Mw of less than 6000 exceeds 90% by mass, the fluidity of the semi-dried ink is too high in the reversal offset printing process, and the ink in the pattern formation by the stencil printing in the process 2 is performed. Crying often occurs, making it difficult to form a fine pattern on the blanket. In addition, the energy ray curable reverse offset printing ink preferably contains less than 20% by mass of energy ray curable resin exceeding Mw 40000 with respect to 100% by mass of the total energy ray curable resin. It is more preferable to contain. If the ratio of the energy ray curable resin exceeding Mw 40000 is too large, the film-forming property of the semi-dried ink coating film is too high, and it becomes difficult to cut out the ink pattern by the drawing plate in the step 2.

With the above ink composition, the unnecessary pattern is stably left from the blanket surface by lightly pressing the convex pattern of the punching plate against the uniform ink semi-dry uniform coating film formed on the blanket in Step 2 above. It can be removed without any problems. Further, in the step 3, the ink pattern formed on the blanket can be stably transferred to the substrate without ink remaining. This is because the ink composition satisfying the specific energy ray curable resin composition requirement of the embodiment, the cohesive force of the ink applied on the blanket and in a semi-dry state, the adhesion force between the ink and the release plate, the blanket adhesion force and the ink It is presumed that the adhesive force between the substrate and the substrate can be stably and easily formed in a state suitable for ink pattern formation and transfer.

In this specification, the weight average molecular weight means a polystyrene equivalent value measured using a gel permeation chromatograph (GPC).

As the energy ray curable polymer and oligomer acrylate having Mw of 6000 to 40,000, various epoxy acrylates, various urethane acrylates, various acrylic resin acrylates, isocyanurate prepolymers and the like can be suitably applied. As these reactive resins, for example, Unidic EPS-832, Unidic V-6850, Unidic V6840, GD15 (all manufactured by DIC Corporation), Tyke Prepolymer (manufactured by Nippon Kasei Chemical Co., Ltd.), Teslac 2300 Teslak 2310, Hitaroid 7851, Hitaroid 7663 (Hitachi Chemical Co., Ltd.), 8KX-012C, 8KX-058, 8KX-077 (Taisei Fine Chemical Co., Ltd.), BAC-45 (Osaka Organic Chemical Co., Ltd.) ))) Can be applied.

The cured film of the active energy ray-curable reverse offset printing ink of the embodiment preferably has a water contact angle of the cured film surface of greater than 95 ° and a contact angle of n-hexadecane of greater than 50 °. Is more preferably 100 ° and the contact angle of n-hexadecane is more than 55 °, more preferably the contact angle of water is more than 105 ° and the contact angle of n-hexadecane is more than 60 °.
The water contact angle of the cured film surface is preferably greater than 95 ° and less than 150 °, and the contact angle of n-hexadecane is preferably greater than 50 ° and less than 100 °, and the water contact angle is greater than 100 ° and less than 150 °. More preferably, the contact angle of n-hexadecane is more than 55 ° and less than 100 °, the contact angle of water is more than 105 ° and less than 150 °, and the contact angle of n-hexadecane is more than 60 ° and more than 100 °. More preferably smaller.
The contact angle on the surface of the cured film of the reverse offset printing ink can be determined by the method described in the examples.

By using the ink of the embodiment of the present invention, it is possible to form a fine and high-quality insulating film pattern having surface liquid repellency comparable to photolithography by a reverse offset printing method. If this technology is applied to the manufacture of various electronic devices, the process for forming fine conductive patterns formed by the photo-etching and pattern plating methods using resist patterns using conventional photolithography technology will be renewed and the price will be reduced. It is possible to create an electronic device having new value. For example, fine bump formation in semiconductor chip mounting technology, various interposers in system packaging technology, and photolithography in pattern plating method applied as fine conductive pattern formation technology such as FO-WLT (Fan-Out Wave Level Package) Can be replaced with a printing method which is a simpler and cheaper process. Further, it is possible to print and form a fine liquid repellent bank pattern that is currently required for forming a color filter or electroluminescent RGB material pattern by an inkjet method. Further, as a simple and inexpensive process for forming a fine conductive pattern, a lyophobic pattern having a fine concave pattern is formed on a substrate using the liquid repellent ink according to the embodiment of the present invention by a reverse offset printing method. A fine conductive pattern can be easily formed by embedding a conductive ink in the concave pattern concave portion or conductive plating. Thereby, for example, it is possible to form a transparent metal mesh that can be applied to antistatic and touch panels, and various fine conductive wirings such as gate electrodes, source / drain electrodes of printed TFTs, and the like.

The liquid repellency is imparted to the ink cured film by adding a liquid repellent component such as a silicone compound or a fluorine compound to the ink. In particular, it is preferable that a liquid-repellent surface is formed simultaneously with ink curing by adding various fluororesins having a functional group that reacts with the energy ray curable resin in the ink. The fluorine-based resin has a feature that an action to minimize the surface free energy of the film works and the fluorine-based resin component segregates on the film surface.

As the fluororesin having these functional groups, a fluororesin having a monofunctional or bifunctional or higher (meth) acryloyl group can be suitably applied. For example, trifluoroethyl acrylate, tetrafluoropropyl acrylate, octafluoropentyl acrylate, octafluoropentyl methacrylate, 2- (perfluorobutyl) ethyl acrylate, 2- (perfluorohexyl) ethyl acrylate, 2- (perfluorobutyl) Some monofunctional acrylates such as ethyl methacrylate, various poly (perfluoroalkyle ether) diacrylates, OX-SQ-F, MAC-SQ-F, AC-SQ-F, etc., some alkyl groups are perfluoro groups Polyfunctional photopolymerizable silsesquioxanes (manufactured by Toagosei Co., Ltd.), PF-3320 (manufactured by Kitamura Chemical Industry Co., Ltd.), UT-UCH23 (manufactured by AGC Seikagaku Co., Ltd.), Fluororeactive oligomeric surfactant Gafakku RS-75, can Megafac RS72-K, Megafac RS-76-E, Megafac RS-76-NS (manufactured by more DIC (Ltd.)) UV photopolymerizable fluorine-based surface modifier, such as apply.

In particular, active energy ray-polymerizable fluorine-based surfactants have excellent solvent solubility, so they have a high degree of freedom in ink design, and are reactively cured with the energy ray-curable resin in the ink and immobilized on the film surface. Since the formed liquid repellent layer can be formed, an insulating film having a liquid repellent layer excellent in solvent resistance, heat resistance, and wear resistance can be formed. In particular, an oligomeric active energy ray-polymerizable fluorosurfactant having an Mw of about 6000 to 10,000 has an effect on improving the pattern forming property and transferability of the ink, and can be more suitably applied. Examples of the oligomeric active energy ray-polymerizable fluorine surfactant include, for example, MegaFac RS-75, MegaFac RS-7-K, MegaFac RS-76-E, MegaFac RS-76-NS, MegaFac. RS-90 (both manufactured by DIC Corporation) and the like can be mentioned.

The active energy ray-curable reverse offset printing ink may contain 1 to 80% by mass of energy ray-polymerizable fluorosurfactant, and 20 to 70% by mass with respect to 100% by mass of the total active energy ray-curable resin in the ink. %, 30 to 60% by mass, or 40 to 55% by mass.
By containing the energy ray polymerizable fluorine-containing surfactant in the above range, the liquid repellency of the cured film can be further improved.

In addition, as an embodiment of the present invention, even if it is commercially available as a surfactant, a fluorosurfactant having active energy ray curability is an active energy ray curable resin in the present specification. It shall be treated as (fluorine resin having a functional group that reacts with the energy ray curable resin).

The line width of the patterning film obtained by reverse offset printing using the ink for reverse offset printing of the embodiment may be 20 μm or less, may be 10 μm or less, and may be 5 μm or less. It may be achievable. The cured film can be formed with a thickness of about 0.1 to 5 μm.

The ink for reverse offset printing according to the embodiment is cured by irradiating the ink coating film formed on the substrate by reverse offset printing with an active energy ray to form a cured film. Various light sources that emit the above-described active energy rays can be used for irradiation with the active energy rays. In addition to electron beams, examples of ultraviolet rays include high-pressure mercury lamps, ultrahigh-pressure mercury lamps, ultraviolet fluorescent lamps, carbon arc lamps, xenon lamps, metal halide lamps, ozone-less UV lamps, and LEDs. Further, the xenon lamp can be used as a flash lamp to use light in the entire wavelength region. If necessary, active energy ray irradiation can be performed under an inert gas such as nitrogen or a rare gas.
Among these, application of UV light by a high-pressure mercury lamp and a metal halide lamp is suitable for crosslinking and curing of various acrylates that are radical polymerization systems and epoxy compounds that are cationic curing systems, and can be suitably applied.

The insulating property of the cured film when the energy beam curable reversal offset ink of the embodiment is applied to various electronic devices is preferably such that the volume resistivity of the cured film is 5 × 10 ¹² Ωcm or more. It is more preferably 10 ¹³ Ωcm or more, and further preferably 1 × 10 ¹⁴ Ωcm or more.

The volume resistivity of the cured film of the reverse offset printing ink can be obtained by the method described in the examples.
The cured film of the reverse offset printing ink that satisfies the above volume resistivity value can be obtained, for example, by adjusting the insulating properties of the resin and other components contained in the reverse offset printing ink.
A cured film of the ink for reverse offset printing that satisfies the above volume resistivity value can be suitably used as an insulating film.

In order to describe the present embodiment in more detail, examples and comparative examples are shown below. These examples specifically illustrate the description of the present embodiment and the effects obtained thereby. Thus, the present embodiment is not limited at all. In addition, each characteristic in the following examples and comparative examples was measured according to the following method.

1. Preparation of Inverted Offset Printing Inks According to the formulations shown in Table 1 below, the inks of Examples 1 to 5 and Comparative Examples 1 to 3 were respectively prepared and mixed. In Table 1, “%” represents mass%. When the surfactant, the UV curable resin, the fine particle powder, and the polymerization initiator are provided including a solvent, each% of the surfactant, each% of the UV curable resin, and each% of the fine particle powder in Table 1 , And each% of the polymerization initiator represents a solid content value (value of dispersion in solvent) as an active ingredient in these materials, and the solvent is described separately in another column.

(Fluorosurfactant)
F555: Fluorine-based non-reactive surface modifier “Megafac” fluorine-containing group / hydrophilic group / lipophilic group-containing oligomer (active ingredient 30% by mass) (manufactured by DIC)

(UV curable resin)
RS-76-E: Fluorine-based UV-reactive surface modifier “Megafac” (active ingredient 40% by mass, Mw≈7000) (manufactured by DIC)
V5500: Epoxy acrylate “Unidic” bisphenol A type epoxy resin base (Mw = 520) (manufactured by DIC)
V6850: “Unidic” UV curable resin (Mw≈30000) (manufactured by DIC)
Aronix M400: Dipentaerythritol hexaacrylate (DPHA) (Mw = 298) (manufactured by Toa Gosei Co., Ltd.)
・ TAIC prepolymer (triallyl isocyanurate polymer, Mw = 20000) (manufactured by Nippon Kasei Co., Ltd.)
GD15: Acrylate (Mw = 62000) (manufactured by DIC)
GD15: acrylate (Mw = 28000) (made by DIC)
GD15: acrylate (Mw = 3200) (manufactured by DIC)
-Light acrylate IAA: Isoamyl acrylate (Mw = 142) (manufactured by Kyoeisha Chemical Co., Ltd.)

(Fine particle powder)
PMA-ST: Organosilica sol (manufactured by Nissan Chemical Industries, Ltd.)

(Polymerization initiator)
・ IRG2959: IRGACURE2959 (BASF)
・ IRG379E: IRGACURE379EG (manufactured by BASF)
・ IRG184: IRGACURE184 (manufactured by BASF)
・ IRG907: IRGACURE907 (manufactured by BASF)

(solvent)
IPAc: isopropyl acetate PGMAc: propylene glycol monomethyl ether acetate MEK / ethyl acetate / MIBK: methyl ethyl ketone / ethyl acetate / methyl isobutyl ketone

The measurement of the weight average molecular weight was obtained under the following conditions using a gel permeation chromatograph (GPC).

Pump; Waters 600 controller
Column; Shodex LF-804 4 linked RI detector; Waters 2414
Data processing; Waters Empower2
Measurement conditions: Column temperature 40 ° C
Solvent Tetrahydrofuran Flow rate 1.0 ml / min standard; Polystyrene sample; 0.4 wt% tetrahydrofuran solution in terms of resin solids filtered through a microfilter

2. Measurement of ink surface tension The surface tension at 25 ° C. of the ink for reversed offset printing of the above example and the ink of the comparative example was measured by a plate method using a surface tension measuring device (model CBUP-A3) manufactured by Kyowa Interface Science Co., Ltd. . The results are shown in Table 1.

3. Preparation of cured film Ink was applied to the release surface (PDMS) of the blanket using a simple coater and left for about 1 minute to form an ink semi-dry film. Next, the slide glass was lightly pressed against the ink surface, and the semi-dry ink was transferred to the glass surface. Subsequently, the ink on the glass was crosslinked with a high-pressure mercury lamp at an integrated illuminance of 1000 mJ / cm ² to prepare a cured ink film.

4). Evaluation of print patterning property The cutability or transferability of the ink coating film on the blanket in the reverse offset printing in the above "3. Production of cured film" was evaluated. The results are shown in Table 1.
Apply a simple coater to the release surface (PDMS) of the blanket in a clean room with a room temperature of about 23 ° C and a humidity of about 45% to form a uniform ink film on the PDMS and adjust the drying time according to the ink composition ( 30 seconds to 300 seconds), an ink semi-dry film was formed. Next, a glass plate (cutting plate) of 5 cm × 5 cm in which convex portions having a line width of 5 μm are arranged in a grid shape is lightly pressed against the ink semi-dry film on the blanket, and the portion corresponding to the pattern of the convex plate convex portion is removed from the ink semi-dry film. By removing, a negative pattern of the punching plate was formed on the blanket. The grid pattern was then transferred from the blanket onto the glass substrate by lightly pressing the grid pattern onto the glass substrate. Next, the ink on the glass substrate was crosslinked and cured with a high-pressure mercury lamp at an integrated illuminance of 1000 mJ / cm ² .
Here, the cutting property (patterning property) of the ink was evaluated by microscopic observation of the ink lattice pattern formed on the blanket at the time of forming the ink semi-dry film pattern by the drawing plate. The ink transferability was evaluated by microscopic observation of the presence or absence of ink remaining on the blanket after pattern transfer to the glass substrate and the shape of the pattern transferred onto the substrate.

Cutting property ◎ ... The pattern of the convex portion of the punched plate was completely removed with high accuracy.
Cutting property x: The pattern of the convex portion of the punched plate was not completely accurately removed.
Transferability A: The patterning film on the blanket was completely transferred to the substrate with high accuracy.
Transferability x: The patterning film on the blanket was not completely transferred to the substrate with high accuracy.

Comparative Example 1: A moderate ink semi-dry state cannot be obtained even after leaving the ink on the blanket for a long time. The ink film could not be completely removed from the ink coating film when the pattern was formed by the punched plate protrusions, and most of the ink corresponding to the protrusions remained on the blanket (ink tearing off). Furthermore, an attempt was made to transfer this incomplete blanket pattern onto a glass substrate, but the ink could not be completely transferred due to tearing of the ink.

Comparative Example 2: When the convex part of the punching plate was pressed against the semi-dry ink film formed on the blanket to remove the ink at a corresponding location and a pattern was formed, the film forming property of the ink coating film was too large and the relief printing plate The ink could not be transferred and cut off.

5). Evaluation of curability (acetone rubbing resistance) Acetone is immersed in a cotton swab, and the same portion (length: about 10 mm) on the surface of each cured film prepared in the above “3. did. The results are shown in Table 1.
A: Scratches and traces could not be confirmed even after 25 reciprocations.

6). Volume resistivity measurement (insulation evaluation)
An ink cured film having a predetermined film thickness (0.5 to 5 μm) was formed on a glass substrate having a chromium pattern previously patterned with a line width of 1 mm by the method for producing a cured film described above.
Next, a vacuum deposition film of Au was formed so as to be orthogonal to the chromium line pattern using a metal mask, and a counter electrode having a facing area of 1 mm ² between chromium and Au was formed by sandwiching the cured film. Using a semiconductor device analyzer (B1500A) manufactured by Agilent Technologies, a voltage of 100 V was applied between the counter electrodes, and the volume resistivity of the film was measured from the measured value of the leakage current of the cured film.

7). Measurement of contact angle Using a contact angle meter drop master (DM-501) manufactured by Kyowa Interface Science Co., Ltd., water or n-hexadecane was added to each cured film produced in “3. Production of cured film” above. The static contact angle between the droplet and the coating film was measured under the condition of 2 μL. The measurement was performed at 25 ° C. The results are shown in Table 1.

As shown in Table 1 above, the inks for reverse offset printing of Examples 1 to 5 can be cured by ultraviolet irradiation, have excellent print patterning properties when applied to reverse offset printing, and have undergone ultraviolet curing. The cured film was also excellent in acetone rubbing resistance and volume resistance (insulating properties).

On the other hand, the inks of Comparative Examples 1 to 3 could not be used for reverse offset printing because the desired print patterning was not obtained when applied to reverse offset printing.

The inks for reverse offset printing of Examples 4 to 5 contained an energy beam polymerizable fluorine-based surfactant and had high liquid repellency with respect to both aqueous and oil-based liquids.

The ink for reversal offset of Example 2 contains fine particle powder (external pigment), so that it mainly contains a UV curable resin having an Mw of less than 6000, and contains a slight amount of a UV curable resin having an Mw of more than 40000. As a result, ink characteristics suitable for reverse offset printing were realized.

The configurations and combinations thereof in the embodiments described above are merely examples, and additions, omissions, substitutions, and other changes can be made without departing from the spirit of the present invention. Further, the present invention is not limited by each embodiment, and is limited only by the scope of the claims.

1 ... Ink coating film, 2 ... Blanket, 3 ... Uncut plate, Substrate ... 4

Claims

An active energy ray curing comprising: a volatile solvent; and an active energy ray curable resin having an active energy ray polymerizable group, wherein the ink has a surface tension of 15 to 27 mN / m at 25 ° C. Reversal offset printing ink.
The extender pigment having a volume average particle diameter of 1 to 150 nm is contained in an amount of 20 to 300% by mass with respect to 100% by mass of the total active energy ray curable resin in the ink for active energy beam curable reversal offset printing. The ink for active energy ray-curable reversal offset printing described in 1.
The active energy ray curable resin having a weight average molecular weight (Mw) of 6000 to 40,000 is 10 to 80% by mass with respect to 100% by mass of the total active energy ray curable resin in the ink for active energy ray curable reversal offset printing. The active energy ray-curable ink for reverse offset printing according to claim 1 or 2, which is contained in
The active energy ray curability according to any one of claims 1 to 3, wherein the water contact angle of the cured film cured by active energy ray irradiation is greater than 95 °, and the contact angle of n-hexadecane is greater than 50 °. Ink for reverse offset printing.
The active energy ray-curable reverse offset printing ink contains 1 to 80% by mass of an energy ray-polymerizable fluorosurfactant with respect to 100% by mass of the total active energy ray-curable resin. The active energy ray-curable reverse offset printing ink according to one item.